121398777 has 16 divisors (see below), whose sum is σ = 180204160. Its totient is φ = 80773200.

The previous prime is 121398773. The next prime is 121398799. The reversal of 121398777 is 777893121.

It is not a de Polignac number, because 121398777 - 2² = 121398773 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (121398773) 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 15 ways as a sum of consecutive naturals, for example, 10452 + ... + 18762.

It is an arithmetic number, because the mean of its divisors is an integer number (11262760).

Almost surely, 2^121398777 is an apocalyptic number.

It is an amenable number.

121398777 is a deficient number, since it is larger than the sum of its proper divisors (58805383).

121398777 is an equidigital number, since it uses as much as digits as its factorization.

121398777 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8861 (or 8855 counting only the distinct ones).

The product of its digits is 148176, while the sum is 45.

The square root of 121398777 is about 11018.1113172812. Note that the first 3 decimals coincide. The cubic root of 121398777 is about 495.1515055062.

The spelling of 121398777 in words is "one hundred twenty-one million, three hundred ninety-eight thousand, seven hundred seventy-seven".