81715039 has 24 divisors (see below), whose sum is σ = 102483968. Its totient is φ = 63745920.

The previous prime is 81715033. The next prime is 81715057. The reversal of 81715039 is 93051718.

It is a happy number.

It is not a de Polignac number, because 81715039 - 2⁹ = 81714527 is a prime.

It is a Smith number, since the sum of its digits (34) coincides with the sum of the digits of its prime factors.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 81714995 and 81715013.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81715033) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 62062 + ... + 63364.

Almost surely, 2^81715039 is an apocalyptic number.

81715039 is a deficient number, since it is larger than the sum of its proper divisors (20768929).

81715039 is a wasteful number, since it uses less digits than its factorization.

81715039 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1375 (or 1358 counting only the distinct ones).

The product of its (nonzero) digits is 7560, while the sum is 34.

The square root of 81715039 is about 9039.6371055480. The cubic root of 81715039 is about 433.9443092903.

The spelling of 81715039 in words is "eighty-one million, seven hundred fifteen thousand, thirty-nine".