9951121979 has 2 divisors, whose sum is σ = 9951121980. Its totient is φ = 9951121978.

The previous prime is 9951121907. The next prime is 9951122033. The reversal of 9951121979 is 9791211599.

9951121979 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 9951121979 - 2²⁸ = 9682686523 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 9951121979.

It is not a weakly prime, because it can be changed into another prime (9951121379) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4975560989 + 4975560990.

It is an arithmetic number, because the mean of its divisors is an integer number (4975560990).

Almost surely, 2^9951121979 is an apocalyptic number.

9951121979 is a deficient number, since it is larger than the sum of its proper divisors (1).

9951121979 is an equidigital number, since it uses as much as digits as its factorization.

9951121979 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 459270, while the sum is 53.

The square root of 9951121979 is about 99755.3105303171. The cubic root of 9951121979 is about 2150.9188053444.

The spelling of 9951121979 in words is "nine billion, nine hundred fifty-one million, one hundred twenty-one thousand, nine hundred seventy-nine".