81577100 has 36 divisors (see below), whose sum is σ = 193117848. Its totient is φ = 29664000.

The previous prime is 81577091. The next prime is 81577103. The reversal of 81577100 is 177518.

It is not an unprimeable number, because it can be changed into a prime (81577103) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 35981 + ... + 38180.

Almost surely, 2^81577100 is an apocalyptic number.

It is an amenable number.

81577100 is an abundant number, since it is smaller than the sum of its proper divisors (111540748).

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

81577100 is a wasteful number, since it uses less digits than its factorization.

81577100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 74186 (or 74179 counting only the distinct ones).

The product of its (nonzero) digits is 1960, while the sum is 29.

The square root of 81577100 is about 9032.0042072621. The cubic root of 81577100 is about 433.6999986656.

The spelling of 81577100 in words is "eighty-one million, five hundred seventy-seven thousand, one hundred".