81339366 has 16 divisors (see below), whose sum is σ = 163867824. Its totient is φ = 26914944.

The previous prime is 81339353. The next prime is 81339371. The reversal of 81339366 is 66393318.

It is a super-2 number, since 2×81339366² = 13232184922563912, which contains 22 as substring.

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, 48655 + ... + 50298.

It is an arithmetic number, because the mean of its divisors is an integer number (10241739).

Almost surely, 2^81339366 is an apocalyptic number.

81339366 is an abundant number, since it is smaller than the sum of its proper divisors (82528458).

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

81339366 is a wasteful number, since it uses less digits than its factorization.

81339366 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 99095.

The product of its digits is 69984, while the sum is 39.

The square root of 81339366 is about 9018.8339601081. The cubic root of 81339366 is about 433.2782889977.

The spelling of 81339366 in words is "eighty-one million, three hundred thirty-nine thousand, three hundred sixty-six".