81125917896 has 32 divisors (see below), whose sum is σ = 204363007200. Its totient is φ = 26835544320.

The previous prime is 81125917877. The next prime is 81125917897. The reversal of 81125917896 is 69871952118.

It is not an unprimeable number, because it can be changed into a prime (81125917897) 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, 12898561 + ... + 12904848.

It is an arithmetic number, because the mean of its divisors is an integer number (6386343975).

Almost surely, 2^81125917896 is an apocalyptic number.

It is an amenable number.

81125917896 is an abundant number, since it is smaller than the sum of its proper divisors (123237089304).

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

81125917896 is a wasteful number, since it uses less digits than its factorization.

81125917896 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25803549 (or 25803545 counting only the distinct ones).

The product of its digits is 2177280, while the sum is 57.

The spelling of 81125917896 in words is "eighty-one billion, one hundred twenty-five million, nine hundred seventeen thousand, eight hundred ninety-six".