79157989 has 2 divisors, whose sum is σ = 79157990. Its totient is φ = 79157988.

The previous prime is 79157893. The next prime is 79157993. The reversal of 79157989 is 98975197.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 51595489 + 27562500 = 7183^2 + 5250^2 .

It is an emirp because it is prime and its reverse (98975197) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 79157989 - 2¹¹ = 79155941 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (79257989) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39578994 + 39578995.

It is an arithmetic number, because the mean of its divisors is an integer number (39578995).

Almost surely, 2^79157989 is an apocalyptic number.

It is an amenable number.

79157989 is a deficient number, since it is larger than the sum of its proper divisors (1).

79157989 is an equidigital number, since it uses as much as digits as its factorization.

79157989 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1428840, while the sum is 55.

The square root of 79157989 is about 8897.0775538938. The cubic root of 79157989 is about 429.3698883499.

The spelling of 79157989 in words is "seventy-nine million, one hundred fifty-seven thousand, nine hundred eighty-nine".