331220220021 has 24 divisors (see below), whose sum is σ = 503816639040. Its totient is φ = 209105755200.

The previous prime is 331220219987. The next prime is 331220220029. The reversal of 331220220021 is 120022022133.

It is a de Polignac number, because none of the positive numbers 2^k-331220220021 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 331220219976 and 331220220003.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (331220220029) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 20656 + ... + 814166.

It is an arithmetic number, because the mean of its divisors is an integer number (20992359960).

Almost surely, 2^331220220021 is an apocalyptic number.

It is an amenable number.

331220220021 is a deficient number, since it is larger than the sum of its proper divisors (172596419019).

331220220021 is a wasteful number, since it uses less digits than its factorization.

331220220021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 795977 (or 795974 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 18.

Adding to 331220220021 its reverse (120022022133), we get a palindrome (451242242154).

The spelling of 331220220021 in words is "three hundred thirty-one billion, two hundred twenty million, two hundred twenty thousand, twenty-one".