81764814 has 16 divisors (see below), whose sum is σ = 163642752. Its totient is φ = 27236088.

The previous prime is 81764791. The next prime is 81764869. The reversal of 81764814 is 41846718.

It is a Curzon number.

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, 6877 + ... + 14519.

It is an arithmetic number, because the mean of its divisors is an integer number (10227672).

Almost surely, 2^81764814 is an apocalyptic number.

81764814 is an abundant number, since it is smaller than the sum of its proper divisors (81877938).

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

81764814 is a wasteful number, since it uses less digits than its factorization.

81764814 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9431.

The product of its digits is 43008, while the sum is 39.

The square root of 81764814 is about 9042.3898389751. The cubic root of 81764814 is about 434.0324007608.

The spelling of 81764814 in words is "eighty-one million, seven hundred sixty-four thousand, eight hundred fourteen".