79781771 has 2 divisors, whose sum is σ = 79781772. Its totient is φ = 79781770.

The previous prime is 79781759. The next prime is 79781797. The reversal of 79781771 is 17718797.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 79781771 - 2¹⁰ = 79780747 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (79781711) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39890885 + 39890886.

It is an arithmetic number, because the mean of its divisors is an integer number (39890886).

Almost surely, 2^79781771 is an apocalyptic number.

79781771 is a deficient number, since it is larger than the sum of its proper divisors (1).

79781771 is an equidigital number, since it uses as much as digits as its factorization.

79781771 is an evil number, because the sum of its binary digits is even.

The product of its digits is 172872, while the sum is 47.

The square root of 79781771 is about 8932.0642071136. The cubic root of 79781771 is about 430.4947810999.

The spelling of 79781771 in words is "seventy-nine million, seven hundred eighty-one thousand, seven hundred seventy-one".