79371581 has 4 divisors (see below), whose sum is σ = 80869212. Its totient is φ = 77873952.

The previous prime is 79371527. The next prime is 79371583. The reversal of 79371581 is 18517397.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 18517397 = 97 ⋅190901.

It can be written as a sum of positive squares in 2 ways, for example, as 63840100 + 15531481 = 7990^2 + 3941^2 .

It is a cyclic number.

It is not a de Polignac number, because 79371581 - 2²⁶ = 12262717 is a prime.

It is a super-2 number, since 2×79371581² = 12599695740879122, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (79371583) 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, 748736 + ... + 748841.

It is an arithmetic number, because the mean of its divisors is an integer number (20217303).

Almost surely, 2^79371581 is an apocalyptic number.

It is an amenable number.

79371581 is a deficient number, since it is larger than the sum of its proper divisors (1497631).

79371581 is a wasteful number, since it uses less digits than its factorization.

79371581 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1497630.

The product of its digits is 52920, while the sum is 41.

The square root of 79371581 is about 8909.0729596294. The cubic root of 79371581 is about 429.7557311047.

The spelling of 79371581 in words is "seventy-nine million, three hundred seventy-one thousand, five hundred eighty-one".