79857187 has 2 divisors, whose sum is σ = 79857188. Its totient is φ = 79857186.

The previous prime is 79857139. The next prime is 79857221. The reversal of 79857187 is 78175897.

It is a strong prime.

It is an emirp because it is prime and its reverse (78175897) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 79857187 - 2⁷ = 79857059 is a prime.

It is not a weakly prime, because it can be changed into another prime (79857487) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39928593 + 39928594.

It is an arithmetic number, because the mean of its divisors is an integer number (39928594).

Almost surely, 2^79857187 is an apocalyptic number.

79857187 is a deficient number, since it is larger than the sum of its proper divisors (1).

79857187 is an equidigital number, since it uses as much as digits as its factorization.

79857187 is an evil number, because the sum of its binary digits is even.

The product of its digits is 987840, while the sum is 52.

The square root of 79857187 is about 8936.2848544571. The cubic root of 79857187 is about 430.6303842145.

The spelling of 79857187 in words is "seventy-nine million, eight hundred fifty-seven thousand, one hundred eighty-seven".