121291979 has 2 divisors, whose sum is σ = 121291980. Its totient is φ = 121291978.

The previous prime is 121291969. The next prime is 121292009. The reversal of 121291979 is 979192121.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-121291979 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (121291969) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 60645989 + 60645990.

It is an arithmetic number, because the mean of its divisors is an integer number (60645990).

Almost surely, 2^121291979 is an apocalyptic number.

121291979 is a deficient number, since it is larger than the sum of its proper divisors (1).

121291979 is an equidigital number, since it uses as much as digits as its factorization.

121291979 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 20412, while the sum is 41.

The square root of 121291979 is about 11013.2637760112. The cubic root of 121291979 is about 495.0062632272.

The spelling of 121291979 in words is "one hundred twenty-one million, two hundred ninety-one thousand, nine hundred seventy-nine".