81382804 has 12 divisors (see below), whose sum is σ = 142844884. Its totient is φ = 40569984.

The previous prime is 81382753. The next prime is 81382811. The reversal of 81382804 is 40828318.

It can be written as a sum of positive squares in 2 ways, for example, as 36626704 + 44756100 = 6052^2 + 6690^2 .

It is a hoax number, since the sum of its digits (34) coincides with the sum of the digits of its distinct prime factors.

It is a self number, because there is not a number n which added to its sum of digits gives 81382804.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 28839 + ... + 31534.

Almost surely, 2^81382804 is an apocalyptic number.

It is an amenable number.

81382804 is a deficient number, since it is larger than the sum of its proper divisors (61462080).

81382804 is a wasteful number, since it uses less digits than its factorization.

81382804 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 60714 (or 60712 counting only the distinct ones).

The product of its (nonzero) digits is 12288, while the sum is 34.

The square root of 81382804 is about 9021.2418213902. The cubic root of 81382804 is about 433.3554037411.

The spelling of 81382804 in words is "eighty-one million, three hundred eighty-two thousand, eight hundred four".