125917255817 has 8 divisors (see below), whose sum is σ = 133372843272. Its totient is φ = 118467078400.

The previous prime is 125917255799. The next prime is 125917255819. The reversal of 125917255817 is 718552719521.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 7192905721 + 118724350096 = 84811^2 + 344564^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 125917255817 - 2²² = 125913061513 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (125917255819) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1304534 + ... + 1397727.

It is an arithmetic number, because the mean of its divisors is an integer number (16671605409).

Almost surely, 2^125917255817 is an apocalyptic number.

125917255817 is a gapful number since it is divisible by the number (17) formed by its first and last digit.

It is an amenable number.

125917255817 is a deficient number, since it is larger than the sum of its proper divisors (7455587455).

125917255817 is a wasteful number, since it uses less digits than its factorization.

125917255817 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2705019.

The product of its digits is 1764000, while the sum is 53.

The spelling of 125917255817 in words is "one hundred twenty-five billion, nine hundred seventeen million, two hundred fifty-five thousand, eight hundred seventeen".