81692868 has 12 divisors (see below), whose sum is σ = 190616720. Its totient is φ = 27230952.

The previous prime is 81692867. The next prime is 81692881. The reversal of 81692868 is 86829618.

It is a tau number, because it is divible by the number of its divisors (12).

It is not an unprimeable number, because it can be changed into a prime (81692867) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3403858 + ... + 3403881.

Almost surely, 2^81692868 is an apocalyptic number.

It is an amenable number.

81692868 is an abundant number, since it is smaller than the sum of its proper divisors (108923852).

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

81692868 is a wasteful number, since it uses less digits than its factorization.

81692868 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6807746 (or 6807744 counting only the distinct ones).

The product of its digits is 331776, while the sum is 48.

The square root of 81692868 is about 9038.4107010027. The cubic root of 81692868 is about 433.9050596832.

The spelling of 81692868 in words is "eighty-one million, six hundred ninety-two thousand, eight hundred sixty-eight".