8131891900 has 36 divisors (see below), whose sum is σ = 19250408520. Its totient is φ = 2957051200.

The previous prime is 8131891897. The next prime is 8131891927. The reversal of 8131891900 is 91981318.

It is a happy number.

It is a super-2 number, since 2×8131891900² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 3695215 + ... + 3697414.

It is an arithmetic number, because the mean of its divisors is an integer number (534733570).

Almost surely, 2^8131891900 is an apocalyptic number.

It is an amenable number.

8131891900 is an abundant number, since it is smaller than the sum of its proper divisors (11118516620).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

8131891900 is a wasteful number, since it uses less digits than its factorization.

8131891900 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7392654 (or 7392647 counting only the distinct ones).

The product of its (nonzero) digits is 15552, while the sum is 40.

The square root of 8131891900 is about 90177.0031659957. The cubic root of 8131891900 is about 2010.9311379318.

The spelling of 8131891900 in words is "eight billion, one hundred thirty-one million, eight hundred ninety-one thousand, nine hundred".