79724189 has 2 divisors, whose sum is σ = 79724190. Its totient is φ = 79724188.

The previous prime is 79724179. The next prime is 79724191. The reversal of 79724189 is 98142797.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 74684164 + 5040025 = 8642^2 + 2245^2 .

It is an emirp because it is prime and its reverse (98142797) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 79724189 - 2⁸ = 79723933 is a prime.

It is a Sophie Germain prime.

Together with 79724191, it forms a pair of twin primes.

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 (79724119) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39862094 + 39862095.

It is an arithmetic number, because the mean of its divisors is an integer number (39862095).

Almost surely, 2^79724189 is an apocalyptic number.

It is an amenable number.

79724189 is a deficient number, since it is larger than the sum of its proper divisors (1).

79724189 is an equidigital number, since it uses as much as digits as its factorization.

79724189 is an evil number, because the sum of its binary digits is even.

The product of its digits is 254016, while the sum is 47.

The square root of 79724189 is about 8928.8402942375. The cubic root of 79724189 is about 430.3911871909.

The spelling of 79724189 in words is "seventy-nine million, seven hundred twenty-four thousand, one hundred eighty-nine".