31994000251 has 2 divisors, whose sum is σ = 31994000252. Its totient is φ = 31994000250.

The previous prime is 31994000243. The next prime is 31994000279. The reversal of 31994000251 is 15200049913.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 31994000251 - 2³ = 31994000243 is a prime.

It is not a weakly prime, because it can be changed into another prime (31994900251) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15997000125 + 15997000126.

It is an arithmetic number, because the mean of its divisors is an integer number (15997000126).

Almost surely, 2^31994000251 is an apocalyptic number.

31994000251 is a deficient number, since it is larger than the sum of its proper divisors (1).

31994000251 is an equidigital number, since it uses as much as digits as its factorization.

31994000251 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 9720, while the sum is 34.

The spelling of 31994000251 in words is "thirty-one billion, nine hundred ninety-four million, two hundred fifty-one", and thus it is an aban number.