81683886 has 16 divisors (see below), whose sum is σ = 164466000. Its totient is φ = 27044928.

The previous prime is 81683873. The next prime is 81683891. The reversal of 81683886 is 68838618.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 44791 + ... + 46578.

It is an arithmetic number, because the mean of its divisors is an integer number (10279125).

Almost surely, 2^81683886 is an apocalyptic number.

81683886 is an abundant number, since it is smaller than the sum of its proper divisors (82782114).

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

81683886 is a wasteful number, since it uses less digits than its factorization.

81683886 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 91523.

The product of its digits is 442368, while the sum is 48.

The square root of 81683886 is about 9037.9138079537. The cubic root of 81683886 is about 433.8891567116.

The spelling of 81683886 in words is "eighty-one million, six hundred eighty-three thousand, eight hundred eighty-six".