311220231021 has 256 divisors, whose sum is σ = 619315200000. Its totient is φ = 150146472960.

The previous prime is 311220230999. The next prime is 311220231109. The reversal of 311220231021 is 120132022113.

311220231021 is a `hidden beast` number, since 311 + 2 + 20 + 2 + 310 + 21 = 666.

It is not a de Polignac number, because 311220231021 - 2¹⁵ = 311220198253 is a prime.

It is a super-2 number, since 2×311220231021² (a number of 24 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 311220230985 and 311220231003.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (311220231121) by changing a digit.

It is a polite number, since it can be written in 255 ways as a sum of consecutive naturals, for example, 88943730 + ... + 88947228.

It is an arithmetic number, because the mean of its divisors is an integer number (2419200000).

Almost surely, 2^311220231021 is an apocalyptic number.

311220231021 is a gapful number since it is divisible by the number (31) formed by its first and last digit.

It is an amenable number.

311220231021 is a deficient number, since it is larger than the sum of its proper divisors (308094968979).

311220231021 is a wasteful number, since it uses less digits than its factorization.

311220231021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3629 (or 3623 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 18.

Adding to 311220231021 its reverse (120132022113), we get a palindrome (431352253134).

The spelling of 311220231021 in words is "three hundred eleven billion, two hundred twenty million, two hundred thirty-one thousand, twenty-one".