679157993 has 2 divisors, whose sum is σ = 679157994. Its totient is φ = 679157992.

The previous prime is 679157933. The next prime is 679158017. The reversal of 679157993 is 399751976.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 669153424 + 10004569 = 25868^2 + 3163^2 .

It is a cyclic number.

It is not a de Polignac number, because 679157993 - 2⁸ = 679157737 is a prime.

It is a super-2 number, since 2×679157993² = 922511158911576098, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (679157933) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 339578996 + 339578997.

It is an arithmetic number, because the mean of its divisors is an integer number (339578997).

Almost surely, 2^679157993 is an apocalyptic number.

It is an amenable number.

679157993 is a deficient number, since it is larger than the sum of its proper divisors (1).

679157993 is an equidigital number, since it uses as much as digits as its factorization.

679157993 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3214890, while the sum is 56.

The square root of 679157993 is about 26060.6598726893. The cubic root of 679157993 is about 879.0028275223.

The spelling of 679157993 in words is "six hundred seventy-nine million, one hundred fifty-seven thousand, nine hundred ninety-three".