126399979 has 2 divisors, whose sum is σ = 126399980. Its totient is φ = 126399978.

The previous prime is 126399971. The next prime is 126400013. The reversal of 126399979 is 979993621.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 126399979 - 2³ = 126399971 is a prime.

It is not a weakly prime, because it can be changed into another prime (126399971) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 63199989 + 63199990.

It is an arithmetic number, because the mean of its divisors is an integer number (63199990).

Almost surely, 2^126399979 is an apocalyptic number.

126399979 is a deficient number, since it is larger than the sum of its proper divisors (1).

126399979 is an equidigital number, since it uses as much as digits as its factorization.

126399979 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1653372, while the sum is 55.

The square root of 126399979 is about 11242.7745241110. The cubic root of 126399979 is about 501.8597130258.

The spelling of 126399979 in words is "one hundred twenty-six million, three hundred ninety-nine thousand, nine hundred seventy-nine".