215640956160 has 864 divisors, whose sum is σ = 921065644800. Its totient is φ = 47578890240.

The previous prime is 215640956143. The next prime is 215640956213. The reversal of 215640956160 is 61659046512.

215640956160 is a `hidden beast` number, since 21 + 5 + 6 + 4 + 0 + 9 + 5 + 616 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (864).

It is a hoax number, since the sum of its digits (45) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 49107565 + ... + 49111955.

It is an arithmetic number, because the mean of its divisors is an integer number (1066048200).

Almost surely, 2^215640956160 is an apocalyptic number.

215640956160 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 215640956160, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (460532822400).

215640956160 is an abundant number, since it is smaller than the sum of its proper divisors (705424688640).

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

215640956160 is a wasteful number, since it uses less digits than its factorization.

215640956160 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4464 (or 4437 counting only the distinct ones).

The product of its (nonzero) digits is 388800, while the sum is 45.

The spelling of 215640956160 in words is "two hundred fifteen billion, six hundred forty million, nine hundred fifty-six thousand, one hundred sixty".