81884736 has 56 divisors (see below), whose sum is σ = 240731040. Its totient is φ = 27294336.

The previous prime is 81884731. The next prime is 81884741. The reversal of 81884736 is 63748818.

It is an interprime number because it is at equal distance from previous prime (81884731) and next prime (81884741).

It is a junction number, because it is equal to n+sod(n) for n = 81884691 and 81884700.

It is not an unprimeable number, because it can be changed into a prime (81884731) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 21966 + ... + 25421.

Almost surely, 2^81884736 is an apocalyptic number.

It is an amenable number.

81884736 is an abundant number, since it is smaller than the sum of its proper divisors (158846304).

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

81884736 is a wasteful number, since it uses less digits than its factorization.

81884736 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 47408 (or 47392 counting only the distinct ones).

The product of its digits is 258048, while the sum is 45.

The square root of 81884736 is about 9049.0185103137. The cubic root of 81884736 is about 434.2444912065.

The spelling of 81884736 in words is "eighty-one million, eight hundred eighty-four thousand, seven hundred thirty-six".