81574868 has 6 divisors (see below), whose sum is σ = 142756026. Its totient is φ = 40787432.

The previous prime is 81574861. The next prime is 81574877. The reversal of 81574868 is 86847518.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 52823824 + 28751044 = 7268^2 + 5362^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81574861) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10196855 + ... + 10196862.

It is an arithmetic number, because the mean of its divisors is an integer number (23792671).

Almost surely, 2^81574868 is an apocalyptic number.

It is an amenable number.

81574868 is a deficient number, since it is larger than the sum of its proper divisors (61181158).

81574868 is a wasteful number, since it uses less digits than its factorization.

81574868 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20393721 (or 20393719 counting only the distinct ones).

The product of its digits is 430080, while the sum is 47.

The square root of 81574868 is about 9031.8806458013. The cubic root of 81574868 is about 433.6960431959.

The spelling of 81574868 in words is "eighty-one million, five hundred seventy-four thousand, eight hundred sixty-eight".