79943861 has 2 divisors, whose sum is σ = 79943862. Its totient is φ = 79943860.

The previous prime is 79943789. The next prime is 79943867. The reversal of 79943861 is 16834997.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 74063236 + 5880625 = 8606^2 + 2425^2 .

It is an emirp because it is prime and its reverse (16834997) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-79943861 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (79943867) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39971930 + 39971931.

It is an arithmetic number, because the mean of its divisors is an integer number (39971931).

Almost surely, 2^79943861 is an apocalyptic number.

It is an amenable number.

79943861 is a deficient number, since it is larger than the sum of its proper divisors (1).

79943861 is an equidigital number, since it uses as much as digits as its factorization.

79943861 is an evil number, because the sum of its binary digits is even.

The product of its digits is 326592, while the sum is 47.

The square root of 79943861 is about 8941.1330937415. The cubic root of 79943861 is about 430.7861245803.

The spelling of 79943861 in words is "seventy-nine million, nine hundred forty-three thousand, eight hundred sixty-one".