81887884 has 24 divisors (see below), whose sum is σ = 155835680. Its totient is φ = 37425024.

The previous prime is 81887863. The next prime is 81887887. The reversal of 81887884 is 48878818.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (52).

It is not an unprimeable number, because it can be changed into a prime (81887887) 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, 2289 + ... + 13000.

Almost surely, 2^81887884 is an apocalyptic number.

It is an amenable number.

81887884 is a deficient number, since it is larger than the sum of its proper divisors (73947796).

81887884 is a wasteful number, since it uses less digits than its factorization.

81887884 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15409 (or 15407 counting only the distinct ones).

The product of its digits is 917504, while the sum is 52.

The square root of 81887884 is about 9049.1924501582. The cubic root of 81887884 is about 434.2500558747.

The spelling of 81887884 in words is "eighty-one million, eight hundred eighty-seven thousand, eight hundred eighty-four".