79980581 has 2 divisors, whose sum is σ = 79980582. Its totient is φ = 79980580.

The previous prime is 79980491. The next prime is 79980583. The reversal of 79980581 is 18508997.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 67092481 + 12888100 = 8191^2 + 3590^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-79980581 is a prime.

It is a super-2 number, since 2×79980581² = 12793786674195122, which contains 22 as substring.

Together with 79980583, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (79980583) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39990290 + 39990291.

It is an arithmetic number, because the mean of its divisors is an integer number (39990291).

Almost surely, 2^79980581 is an apocalyptic number.

It is an amenable number.

79980581 is a deficient number, since it is larger than the sum of its proper divisors (1).

79980581 is an equidigital number, since it uses as much as digits as its factorization.

79980581 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 181440, while the sum is 47.

The square root of 79980581 is about 8943.1862890136. The cubic root of 79980581 is about 430.8520710457.

The spelling of 79980581 in words is "seventy-nine million, nine hundred eighty thousand, five hundred eighty-one".