231221200020 has 96 divisors (see below), whose sum is σ = 695158039296. Its totient is φ = 57214617600.

The previous prime is 231221200013. The next prime is 231221200039. The reversal of 231221200020 is 20002122132.

It is a happy number.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1523971 + ... + 1668810.

It is an arithmetic number, because the mean of its divisors is an integer number (7241229576).

Almost surely, 2^231221200020 is an apocalyptic number.

231221200020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

231221200020 is an abundant number, since it is smaller than the sum of its proper divisors (463936839276).

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

231221200020 is a wasteful number, since it uses less digits than its factorization.

231221200020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3192881 (or 3192879 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 15.

Adding to 231221200020 its reverse (20002122132), we get a palindrome (251223322152).

The spelling of 231221200020 in words is "two hundred thirty-one billion, two hundred twenty-one million, two hundred thousand, twenty".