81362916 has 18 divisors (see below), whose sum is σ = 205667462. Its totient is φ = 27120960.

The previous prime is 81362903. The next prime is 81362927. The reversal of 81362916 is 61926318.

81362916 is a `hidden beast` number, since 8 + 13 + 629 + 16 = 666.

It can be written as a sum of positive squares in only one way, i.e., 72182016 + 9180900 = 8496^2 + 3030^2 .

It is a tau number, because it is divible by the number of its divisors (18).

It is a Harshad number since it is a multiple of its sum of digits (36), and also a Moran number because the ratio is a prime number: 2260081 = 81362916 / (8 + 1 + 3 + 6 + 2 + 9 + 1 + 6).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1130005 + ... + 1130076.

Almost surely, 2^81362916 is an apocalyptic number.

It is an amenable number.

81362916 is an abundant number, since it is smaller than the sum of its proper divisors (124304546).

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

81362916 is a wasteful number, since it uses less digits than its factorization.

81362916 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2260091 (or 2260086 counting only the distinct ones).

The product of its digits is 15552, while the sum is 36.

The square root of 81362916 is about 9020.1394667710. The cubic root of 81362916 is about 433.3201003191.

The spelling of 81362916 in words is "eighty-one million, three hundred sixty-two thousand, nine hundred sixteen".