31800635989 has 2 divisors, whose sum is σ = 31800635990. Its totient is φ = 31800635988.

The previous prime is 31800635987. The next prime is 31800636001. The reversal of 31800635989 is 98953600813.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 31609284100 + 191351889 = 177790^2 + 13833^2 .

It is a cyclic number.

It is not a de Polignac number, because 31800635989 - 2¹ = 31800635987 is a prime.

It is a super-2 number, since 2×31800635989² (a number of 22 digits) contains 22 as substring.

Together with 31800635987, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31800635987) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15900317994 + 15900317995.

It is an arithmetic number, because the mean of its divisors is an integer number (15900317995).

Almost surely, 2^31800635989 is an apocalyptic number.

It is an amenable number.

31800635989 is a deficient number, since it is larger than the sum of its proper divisors (1).

31800635989 is an equidigital number, since it uses as much as digits as its factorization.

31800635989 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1399680, while the sum is 52.

The spelling of 31800635989 in words is "thirty-one billion, eight hundred million, six hundred thirty-five thousand, nine hundred eighty-nine".