667963979 has 2 divisors, whose sum is σ = 667963980. Its totient is φ = 667963978.

The previous prime is 667963963. The next prime is 667964027. The reversal of 667963979 is 979369766.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 667963979 - 2⁴ = 667963963 is a prime.

It is not a weakly prime, because it can be changed into another prime (667963909) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 333981989 + 333981990.

It is an arithmetic number, because the mean of its divisors is an integer number (333981990).

Almost surely, 2^667963979 is an apocalyptic number.

667963979 is a deficient number, since it is larger than the sum of its proper divisors (1).

667963979 is an equidigital number, since it uses as much as digits as its factorization.

667963979 is an evil number, because the sum of its binary digits is even.

The product of its digits is 23147208, while the sum is 62.

The square root of 667963979 is about 25844.9991100793. Note that the first 3 decimals coincide. The cubic root of 667963979 is about 874.1467509255.

The spelling of 667963979 in words is "six hundred sixty-seven million, nine hundred sixty-three thousand, nine hundred seventy-nine".