679131217 has 2 divisors, whose sum is σ = 679131218. Its totient is φ = 679131216.

The previous prime is 679131203. The next prime is 679131227. The reversal of 679131217 is 712131976.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 555120721 + 124010496 = 23561^2 + 11136^2 .

It is a cyclic number.

It is not a de Polignac number, because 679131217 - 2¹¹ = 679129169 is a prime.

It is a super-2 number, since 2×679131217² = 922438419807802178, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (679131227) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 339565608 + 339565609.

It is an arithmetic number, because the mean of its divisors is an integer number (339565609).

Almost surely, 2^679131217 is an apocalyptic number.

It is an amenable number.

679131217 is a deficient number, since it is larger than the sum of its proper divisors (1).

679131217 is an equidigital number, since it uses as much as digits as its factorization.

679131217 is an evil number, because the sum of its binary digits is even.

The product of its digits is 15876, while the sum is 37.

The square root of 679131217 is about 26060.1461431052. The cubic root of 679131217 is about 878.9912757237.

The spelling of 679131217 in words is "six hundred seventy-nine million, one hundred thirty-one thousand, two hundred seventeen".