81659037 has 16 divisors (see below), whose sum is σ = 112145600. Its totient is φ = 52814592.

The previous prime is 81659033. The next prime is 81659051. The reversal of 81659037 is 73095618.

It is not a de Polignac number, because 81659037 - 2² = 81659033 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 81658986 and 81659004.

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 pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 47214 + ... + 48912.

It is an arithmetic number, because the mean of its divisors is an integer number (7009100).

Almost surely, 2^81659037 is an apocalyptic number.

It is an amenable number.

81659037 is a deficient number, since it is larger than the sum of its proper divisors (30486563).

81659037 is a wasteful number, since it uses less digits than its factorization.

81659037 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2172.

The product of its (nonzero) digits is 45360, while the sum is 39.

The square root of 81659037 is about 9036.5389945487. The cubic root of 81659037 is about 433.8451545398.

The spelling of 81659037 in words is "eighty-one million, six hundred fifty-nine thousand, thirty-seven".