81889602 has 8 divisors (see below), whose sum is σ = 163779216. Its totient is φ = 27296532.

The previous prime is 81889597. The next prime is 81889603. The reversal of 81889602 is 20698818.

It is a sphenic number, since it is the product of 3 distinct primes.

81889602 is an admirable number.

It is a Smith number, since the sum of its digits (42) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is not an unprimeable number, because it can be changed into a prime (81889603) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6824128 + ... + 6824139.

It is an arithmetic number, because the mean of its divisors is an integer number (20472402).

Almost surely, 2^81889602 is an apocalyptic number.

81889602 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

81889602 is a wasteful number, since it uses less digits than its factorization.

81889602 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13648272.

The product of its (nonzero) digits is 55296, while the sum is 42.

The square root of 81889602 is about 9049.2873752578. The cubic root of 81889602 is about 434.2530926950.

The spelling of 81889602 in words is "eighty-one million, eight hundred eighty-nine thousand, six hundred two".