231031221000 has 64 divisors (see below), whose sum is σ = 720817418880. Its totient is φ = 61608324800.

The previous prime is 231031220977. The next prime is 231031221011. The reversal of 231031221000 is 122130132.

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

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 38502204 + ... + 38508203.

It is an arithmetic number, because the mean of its divisors is an integer number (11262772170).

Almost surely, 2^231031221000 is an apocalyptic number.

231031221000 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

231031221000 is an abundant number, since it is smaller than the sum of its proper divisors (489786197880).

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

231031221000 is a wasteful number, since it uses less digits than its factorization.

231031221000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 77010431 (or 77010417 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 15.

Adding to 231031221000 its reverse (122130132), we get a palindrome (231153351132).

The spelling of 231031221000 in words is "two hundred thirty-one billion, thirty-one million, two hundred twenty-one thousand".