81802645 has 16 divisors (see below), whose sum is σ = 102855168. Its totient is φ = 62377920.

The previous prime is 81802603. The next prime is 81802663. The reversal of 81802645 is 54620818.

It is not a de Polignac number, because 81802645 - 2⁷ = 81802517 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 81802645.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 6447 + ... + 14323.

It is an arithmetic number, because the mean of its divisors is an integer number (6428448).

Almost surely, 2^81802645 is an apocalyptic number.

It is an amenable number.

81802645 is a deficient number, since it is larger than the sum of its proper divisors (21052523).

81802645 is a wasteful number, since it uses less digits than its factorization.

81802645 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7980.

The product of its (nonzero) digits is 15360, while the sum is 34.

The square root of 81802645 is about 9044.4814666182. The cubic root of 81802645 is about 434.0993299088.

The spelling of 81802645 in words is "eighty-one million, eight hundred two thousand, six hundred forty-five".