81659036 has 12 divisors (see below), whose sum is σ = 150424680. Its totient is φ = 38680560.

The previous prime is 81659033. The next prime is 81659051. The reversal of 81659036 is 63095618.

It is a Harshad number since it is a multiple of its sum of digits (38).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81659033) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 537155 + ... + 537306.

It is an arithmetic number, because the mean of its divisors is an integer number (12535390).

Almost surely, 2^81659036 is an apocalyptic number.

It is an amenable number.

81659036 is a deficient number, since it is larger than the sum of its proper divisors (68765644).

81659036 is a wasteful number, since it uses less digits than its factorization.

81659036 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1074484 (or 1074482 counting only the distinct ones).

The product of its (nonzero) digits is 38880, while the sum is 38.

The square root of 81659036 is about 9036.5389392178. The cubic root of 81659036 is about 433.8451527689.

The spelling of 81659036 in words is "eighty-one million, six hundred fifty-nine thousand, thirty-six".