67399979 has 2 divisors, whose sum is σ = 67399980. Its totient is φ = 67399978.

The previous prime is 67399961. The next prime is 67399991. The reversal of 67399979 is 97999376.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 67399979 - 2⁸ = 67399723 is a prime.

It is not a weakly prime, because it can be changed into another prime (67399909) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33699989 + 33699990.

It is an arithmetic number, because the mean of its divisors is an integer number (33699990).

Almost surely, 2^67399979 is an apocalyptic number.

67399979 is a deficient number, since it is larger than the sum of its proper divisors (1).

67399979 is an equidigital number, since it uses as much as digits as its factorization.

67399979 is an evil number, because the sum of its binary digits is even.

The product of its digits is 5786802, while the sum is 59.

The square root of 67399979 is about 8209.7490217424. The cubic root of 67399979 is about 406.9614328770.

The spelling of 67399979 in words is "sixty-seven million, three hundred ninety-nine thousand, nine hundred seventy-nine".