71986815 has 12 divisors (see below), whose sum is σ = 124777224. Its totient is φ = 38392944.

The previous prime is 71986807. The next prime is 71986847. The reversal of 71986815 is 51868917.

It is not a de Polignac number, because 71986815 - 2³ = 71986807 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45), and also a Moran number because the ratio is a prime number: 1599707 = 71986815 / (7 + 1 + 9 + 8 + 6 + 8 + 1 + 5).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 799809 + ... + 799898.

It is an arithmetic number, because the mean of its divisors is an integer number (10398102).

Almost surely, 2^71986815 is an apocalyptic number.

71986815 is a deficient number, since it is larger than the sum of its proper divisors (52790409).

71986815 is a wasteful number, since it uses less digits than its factorization.

71986815 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1599718 (or 1599715 counting only the distinct ones).

The product of its digits is 120960, while the sum is 45.

The square root of 71986815 is about 8484.5044050905. The cubic root of 71986815 is about 415.9913687034.

The spelling of 71986815 in words is "seventy-one million, nine hundred eighty-six thousand, eight hundred fifteen".