71864581 has 16 divisors (see below), whose sum is σ = 78168960. Its totient is φ = 65862720.

The previous prime is 71864579. The next prime is 71864587. The reversal of 71864581 is 18546817.

It is a cyclic number.

It is not a de Polignac number, because 71864581 - 2¹ = 71864579 is a prime.

It is a super-2 number, since 2×71864581² = 10329036004611122, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (71864587) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 108391 + ... + 109051.

It is an arithmetic number, because the mean of its divisors is an integer number (4885560).

Almost surely, 2^71864581 is an apocalyptic number.

It is an amenable number.

71864581 is a deficient number, since it is larger than the sum of its proper divisors (6304379).

71864581 is a wasteful number, since it uses less digits than its factorization.

71864581 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 876.

The product of its digits is 53760, while the sum is 40.

The square root of 71864581 is about 8477.2979775398. The cubic root of 71864581 is about 415.7557834491.

The spelling of 71864581 in words is "seventy-one million, eight hundred sixty-four thousand, five hundred eighty-one".