31633228021 has 2 divisors, whose sum is σ = 31633228022. Its totient is φ = 31633228020.

The previous prime is 31633227971. The next prime is 31633228069. The reversal of 31633228021 is 12082233613.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 28930267921 + 2702960100 = 170089^2 + 51990^2 .

It is a cyclic number.

It is not a de Polignac number, because 31633228021 - 2²³ = 31624839413 is a prime.

It is a super-2 number, since 2×31633228021² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31633222021) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15816614010 + 15816614011.

It is an arithmetic number, because the mean of its divisors is an integer number (15816614011).

Almost surely, 2^31633228021 is an apocalyptic number.

It is an amenable number.

31633228021 is a deficient number, since it is larger than the sum of its proper divisors (1).

31633228021 is an equidigital number, since it uses as much as digits as its factorization.

31633228021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 10368, while the sum is 31.

The spelling of 31633228021 in words is "thirty-one billion, six hundred thirty-three million, two hundred twenty-eight thousand, twenty-one".