121129979 has 4 divisors (see below), whose sum is σ = 122491080. Its totient is φ = 119768880.

The previous prime is 121129919. The next prime is 121130003. The reversal of 121129979 is 979921121.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-121129979 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (121129909) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 680417 + ... + 680594.

It is an arithmetic number, because the mean of its divisors is an integer number (30622770).

Almost surely, 2^121129979 is an apocalyptic number.

121129979 is a deficient number, since it is larger than the sum of its proper divisors (1361101).

121129979 is an equidigital number, since it uses as much as digits as its factorization.

121129979 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1361100.

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

The square root of 121129979 is about 11005.9065505755. The cubic root of 121129979 is about 494.7857849417.

The spelling of 121129979 in words is "one hundred twenty-one million, one hundred twenty-nine thousand, nine hundred seventy-nine".