121660255779 has 16 divisors (see below), whose sum is σ = 162684792480. Its totient is φ = 80871436800.

The previous prime is 121660255741. The next prime is 121660255789. The reversal of 121660255779 is 977552066121.

It is not a de Polignac number, because 121660255779 - 2⁹ = 121660255267 is a prime.

It is not an unprimeable number, because it can be changed into a prime (121660255709) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3317757 + ... + 3354225.

It is an arithmetic number, because the mean of its divisors is an integer number (10167799530).

Almost surely, 2^121660255779 is an apocalyptic number.

121660255779 is a deficient number, since it is larger than the sum of its proper divisors (41024536701).

121660255779 is a wasteful number, since it uses less digits than its factorization.

121660255779 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 39670.

The product of its (nonzero) digits is 1587600, while the sum is 51.

The spelling of 121660255779 in words is "one hundred twenty-one billion, six hundred sixty million, two hundred fifty-five thousand, seven hundred seventy-nine".