309868961 has 2 divisors, whose sum is σ = 309868962. Its totient is φ = 309868960.

The previous prime is 309868943. The next prime is 309868991. The reversal of 309868961 is 169868903.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 308353600 + 1515361 = 17560^2 + 1231^2 .

It is a cyclic number.

It is not a de Polignac number, because 309868961 - 2²⁶ = 242760097 is a prime.

It is not a weakly prime, because it can be changed into another prime (309868931) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 154934480 + 154934481.

It is an arithmetic number, because the mean of its divisors is an integer number (154934481).

Almost surely, 2^309868961 is an apocalyptic number.

It is an amenable number.

309868961 is a deficient number, since it is larger than the sum of its proper divisors (1).

309868961 is an equidigital number, since it uses as much as digits as its factorization.

309868961 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 559872, while the sum is 50.

The square root of 309868961 is about 17603.0952107861. The cubic root of 309868961 is about 676.6945706122.

The spelling of 309868961 in words is "three hundred nine million, eight hundred sixty-eight thousand, nine hundred sixty-one".