81693586 has 24 divisors (see below), whose sum is σ = 133341120. Its totient is φ = 37520496.

The previous prime is 81693581. The next prime is 81693613. The reversal of 81693586 is 68539618.

It is not an unprimeable number, because it can be changed into a prime (81693581) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 88435 + ... + 89353.

It is an arithmetic number, because the mean of its divisors is an integer number (5555880).

Almost surely, 2^81693586 is an apocalyptic number.

81693586 is a deficient number, since it is larger than the sum of its proper divisors (51647534).

81693586 is a wasteful number, since it uses less digits than its factorization.

81693586 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1210 (or 1197 counting only the distinct ones).

The product of its digits is 311040, while the sum is 46.

The square root of 81693586 is about 9038.4504202878. The cubic root of 81693586 is about 433.9063308791.

The spelling of 81693586 in words is "eighty-one million, six hundred ninety-three thousand, five hundred eighty-six".