100991389925 has 24 divisors (see below), whose sum is σ = 131604972576. Its totient is φ = 76781355840.

The previous prime is 100991389921. The next prime is 100991389927. The reversal of 100991389925 is 529983199001.

It is not a de Polignac number, because 100991389925 - 2² = 100991389921 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (100991389921) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1229759 + ... + 1309308.

It is an arithmetic number, because the mean of its divisors is an integer number (5483540524).

Almost surely, 2^100991389925 is an apocalyptic number.

It is an amenable number.

100991389925 is a deficient number, since it is larger than the sum of its proper divisors (30613582651).

100991389925 is a wasteful number, since it uses less digits than its factorization.

100991389925 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2539157 (or 2539152 counting only the distinct ones).

The product of its (nonzero) digits is 1574640, while the sum is 56.

The spelling of 100991389925 in words is "one hundred billion, nine hundred ninety-one million, three hundred eighty-nine thousand, nine hundred twenty-five".