121620779 has 4 divisors (see below), whose sum is σ = 138995184. Its totient is φ = 104246376.

The previous prime is 121620773. The next prime is 121620787. The reversal of 121620779 is 977026121.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 977026121 = 199 ⋅4909679.

It is a cyclic number.

It is not a de Polignac number, because 121620779 - 2⁸ = 121620523 is a prime.

It is a super-2 number, since 2×121620779² = 29583227769133682, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (121620773) 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, 8687192 + ... + 8687205.

It is an arithmetic number, because the mean of its divisors is an integer number (34748796).

Almost surely, 2^121620779 is an apocalyptic number.

121620779 is a deficient number, since it is larger than the sum of its proper divisors (17374405).

121620779 is an equidigital number, since it uses as much as digits as its factorization.

121620779 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17374404.

The product of its (nonzero) digits is 10584, while the sum is 35.

The square root of 121620779 is about 11028.1811283638. The cubic root of 121620779 is about 495.4531496381.

The spelling of 121620779 in words is "one hundred twenty-one million, six hundred twenty thousand, seven hundred seventy-nine".