81362805 has 32 divisors (see below), whose sum is σ = 132979968. Its totient is φ = 42470400.

The previous prime is 81362789. The next prime is 81362843. The reversal of 81362805 is 50826318.

It is a happy number.

It is not a de Polignac number, because 81362805 - 2⁴ = 81362789 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 256507 + ... + 256823.

It is an arithmetic number, because the mean of its divisors is an integer number (4155624).

Almost surely, 2^81362805 is an apocalyptic number.

It is an amenable number.

81362805 is a deficient number, since it is larger than the sum of its proper divisors (51617163).

81362805 is a wasteful number, since it uses less digits than its factorization.

81362805 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 637.

The product of its (nonzero) digits is 11520, while the sum is 33.

The square root of 81362805 is about 9020.1333138707. The cubic root of 81362805 is about 433.3199032656.

The spelling of 81362805 in words is "eighty-one million, three hundred sixty-two thousand, eight hundred five".