67979999 has 2 divisors, whose sum is σ = 67980000. Its totient is φ = 67979998.

The previous prime is 67979987. The next prime is 67980013. The reversal of 67979999 is 99997976.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 67979999 - 2⁴ = 67979983 is a prime.

It is a Chen prime.

67979999 is a modest number, since divided by 9999 gives 6797 as remainder.

It is a plaindrome in base 13.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (67979959) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33989999 + 33990000.

It is an arithmetic number, because the mean of its divisors is an integer number (33990000).

Almost surely, 2^67979999 is an apocalyptic number.

67979999 is a deficient number, since it is larger than the sum of its proper divisors (1).

67979999 is an equidigital number, since it uses as much as digits as its factorization.

67979999 is an evil number, because the sum of its binary digits is even.

The product of its digits is 17360406, while the sum is 65.

The square root of 67979999 is about 8244.9984232867. The cubic root of 67979999 is about 408.1254880402.

The spelling of 67979999 in words is "sixty-seven million, nine hundred seventy-nine thousand, nine hundred ninety-nine".