125617268983921 has 45 divisors (see below), whose sum is σ = 149605856460263. Its totient is φ = 105395608512480.

The previous prime is 125617268983909. The next prime is 125617268983933. The reversal of 125617268983921 is 129389862716521.

The square root of 125617268983921 is 11207911.

It is a perfect power (a square), and thus also a powerful number.

It is an interprime number because it is at equal distance from previous prime (125617268983909) and next prime (125617268983933).

It can be written as a sum of positive squares in 7 ways, for example, as 93372815287521 + 32244453696400 = 9662961^2 + 5678420^2 .

It is not a de Polignac number, because 125617268983921 - 2¹⁹ = 125617268459633 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (125617268986921) by changing a digit.

It is a polite number, since it can be written in 44 ways as a sum of consecutive naturals, for example, 20835503535 + ... + 20835509563.

Almost surely, 2^{125617268983921} is an apocalyptic number.

125617268983921 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

125617268983921 is the 11207911-st square number.

125617268983921 is the 5603956-th centered octagonal number.

It is an amenable number.

125617268983921 is a deficient number, since it is larger than the sum of its proper divisors (23988587476342).

125617268983921 is an frugal number, since it uses more digits than its factorization.

125617268983921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12132 (or 6053 counting only the distinct ones).

The product of its digits is 156764160, while the sum is 70.

The spelling of 125617268983921 in words is "one hundred twenty-five trillion, six hundred seventeen billion, two hundred sixty-eight million, nine hundred eighty-three thousand, nine hundred twenty-one".