231221321020 has 12 divisors (see below), whose sum is σ = 485564774184. Its totient is φ = 92488528400.

The previous prime is 231221321011. The next prime is 231221321059. The reversal of 231221321020 is 20123122132.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5780533006 + ... + 5780533045.

It is an arithmetic number, because the mean of its divisors is an integer number (40463731182).

Almost surely, 2^231221321020 is an apocalyptic number.

231221321020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

231221321020 is an abundant number, since it is smaller than the sum of its proper divisors (254343453164).

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

231221321020 is a wasteful number, since it uses less digits than its factorization.

231221321020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11561066060 (or 11561066058 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 19.

Adding to 231221321020 its reverse (20123122132), we get a palindrome (251344443152).

The spelling of 231221321020 in words is "two hundred thirty-one billion, two hundred twenty-one million, three hundred twenty-one thousand, twenty".