231556216320 has 1920 divisors, whose sum is σ = 1035968693760. Its totient is φ = 48731258880.

The previous prime is 231556216319. The next prime is 231556216321. The reversal of 231556216320 is 23612655132.

231556216320 is a `hidden beast` number, since 2 + 3 + 1 + 5 + 5 + 621 + 6 + 3 + 20 = 666.

231556216320 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (231556216319) and next prime (231556216321).

It is a tau number, because it is divible by the number of its divisors (1920).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (231556216321) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 1690191292 + ... + 1690191428.

It is an arithmetic number, because the mean of its divisors is an integer number (539567028).

Almost surely, 2^231556216320 is an apocalyptic number.

231556216320 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 231556216320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (517984346880).

231556216320 is an abundant number, since it is smaller than the sum of its proper divisors (804412477440).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

231556216320 is a wasteful number, since it uses less digits than its factorization.

231556216320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 218 (or 190 counting only the distinct ones).

The product of its (nonzero) digits is 64800, while the sum is 36.

The spelling of 231556216320 in words is "two hundred thirty-one billion, five hundred fifty-six million, two hundred sixteen thousand, three hundred twenty".