679987261 has 2 divisors, whose sum is σ = 679987262. Its totient is φ = 679987260.

The previous prime is 679987177. The next prime is 679987279. The reversal of 679987261 is 162789976.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 402764761 + 277222500 = 20069^2 + 16650^2 .

It is a cyclic number.

It is not a de Polignac number, because 679987261 - 2¹⁵ = 679954493 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (679981261) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 339993630 + 339993631.

It is an arithmetic number, because the mean of its divisors is an integer number (339993631).

Almost surely, 2^679987261 is an apocalyptic number.

It is an amenable number.

679987261 is a deficient number, since it is larger than the sum of its proper divisors (1).

679987261 is an equidigital number, since it uses as much as digits as its factorization.

679987261 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2286144, while the sum is 55.

The square root of 679987261 is about 26076.5653604918. The cubic root of 679987261 is about 879.3604431019.

The spelling of 679987261 in words is "six hundred seventy-nine million, nine hundred eighty-seven thousand, two hundred sixty-one".