79581181 has 2 divisors, whose sum is σ = 79581182. Its totient is φ = 79581180.

The previous prime is 79581179. The next prime is 79581221. The reversal of 79581181 is 18118597.

It is an a-pointer prime, because the next prime (79581221) can be obtained adding 79581181 to its sum of digits (40).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 79032100 + 549081 = 8890^2 + 741^2 .

It is a cyclic number.

It is not a de Polignac number, because 79581181 - 2¹ = 79581179 is a prime.

It is a super-2 number, since 2×79581181² = 12666328738709522, which contains 22 as substring.

Together with 79581179, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (79581781) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39790590 + 39790591.

It is an arithmetic number, because the mean of its divisors is an integer number (39790591).

Almost surely, 2^79581181 is an apocalyptic number.

It is an amenable number.

79581181 is a deficient number, since it is larger than the sum of its proper divisors (1).

79581181 is an equidigital number, since it uses as much as digits as its factorization.

79581181 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 20160, while the sum is 40.

The square root of 79581181 is about 8920.8284929148. The cubic root of 79581181 is about 430.1336901773.

The spelling of 79581181 in words is "seventy-nine million, five hundred eighty-one thousand, one hundred eighty-one".