231031320 has 256 divisors, whose sum is σ = 801239040. Its totient is φ = 52850688.

The previous prime is 231031319. The next prime is 231031321. The reversal of 231031320 is 23130132.

231031320 = T₁₉ + T₂₀ + ... + T₁₁₁₄.

It is an interprime number because it is at equal distance from previous prime (231031319) and next prime (231031321).

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a self number, because there is not a number n which added to its sum of digits gives 231031320.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (231031321) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 1686292 + ... + 1686428.

It is an arithmetic number, because the mean of its divisors is an integer number (3129840).

Almost surely, 2^231031320 is an apocalyptic number.

231031320 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 231031320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (400619520).

231031320 is an abundant number, since it is smaller than the sum of its proper divisors (570207720).

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

231031320 is a wasteful number, since it uses less digits than its factorization.

231031320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 234 (or 230 counting only the distinct ones).

The product of its (nonzero) digits is 108, while the sum is 15.

The square root of 231031320 is about 15199.7144710024. The cubic root of 231031320 is about 613.6069733074.

Adding to 231031320 its reverse (23130132), we get a palindrome (254161452).

The spelling of 231031320 in words is "two hundred thirty-one million, thirty-one thousand, three hundred twenty".