81396582 has 16 divisors (see below), whose sum is σ = 163110720. Its totient is φ = 27079272.

The previous prime is 81396571. The next prime is 81396583. The reversal of 81396582 is 28569318.

It is a super-2 number, since 2×81396582² = 13250807122565448, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81396583) 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, 9832 + ... + 16107.

It is an arithmetic number, because the mean of its divisors is an integer number (10194420).

Almost surely, 2^81396582 is an apocalyptic number.

81396582 is an abundant number, since it is smaller than the sum of its proper divisors (81714138).

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

81396582 is a wasteful number, since it uses less digits than its factorization.

81396582 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26467.

The product of its digits is 103680, while the sum is 42.

The square root of 81396582 is about 9022.0054311666. The cubic root of 81396582 is about 433.3798578581.

The spelling of 81396582 in words is "eighty-one million, three hundred ninety-six thousand, five hundred eighty-two".