81435558828 has 36 divisors (see below), whose sum is σ = 205757304648. Its totient is φ = 25057094400.

The previous prime is 81435558791. The next prime is 81435558857. The reversal of 81435558828 is 82885553418.

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, 20075773 + ... + 20079828.

Almost surely, 2^81435558828 is an apocalyptic number.

It is an amenable number.

81435558828 is an abundant number, since it is smaller than the sum of its proper divisors (124321745820).

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

81435558828 is a wasteful number, since it uses less digits than its factorization.

81435558828 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40155634 (or 40155619 counting only the distinct ones).

The product of its digits is 12288000, while the sum is 57.

The spelling of 81435558828 in words is "eighty-one billion, four hundred thirty-five million, five hundred fifty-eight thousand, eight hundred twenty-eight".