239861905897 has 2 divisors, whose sum is σ = 239861905898. Its totient is φ = 239861905896.

The previous prime is 239861905879. The next prime is 239861905961. The reversal of 239861905897 is 798509168932.

Together with previous prime (239861905879) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 227151372816 + 12710533081 = 476604^2 + 112741^2 .

It is a cyclic number.

It is not a de Polignac number, because 239861905897 - 2³⁵ = 205502167529 is a prime.

It is not a weakly prime, because it can be changed into another prime (239861906897) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 119930952948 + 119930952949.

It is an arithmetic number, because the mean of its divisors is an integer number (119930952949).

Almost surely, 2^239861905897 is an apocalyptic number.

It is an amenable number.

239861905897 is a deficient number, since it is larger than the sum of its proper divisors (1).

239861905897 is an equidigital number, since it uses as much as digits as its factorization.

239861905897 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 58786560, while the sum is 67.

The spelling of 239861905897 in words is "two hundred thirty-nine billion, eight hundred sixty-one million, nine hundred five thousand, eight hundred ninety-seven".