125137513891 has 4 divisors (see below), whose sum is σ = 134763476512. Its totient is φ = 115511551272.

The previous prime is 125137513889. The next prime is 125137513901. The reversal of 125137513891 is 198315731521.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 198315731521 = 8353 ⋅23741857.

It is not a de Polignac number, because 125137513891 - 2¹ = 125137513889 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (125137513811) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4812981291 + ... + 4812981316.

It is an arithmetic number, because the mean of its divisors is an integer number (33690869128).

Almost surely, 2^125137513891 is an apocalyptic number.

125137513891 is a deficient number, since it is larger than the sum of its proper divisors (9625962621).

125137513891 is an equidigital number, since it uses as much as digits as its factorization.

125137513891 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9625962620.

The product of its digits is 226800, while the sum is 46.

The spelling of 125137513891 in words is "one hundred twenty-five billion, one hundred thirty-seven million, five hundred thirteen thousand, eight hundred ninety-one".