121561877 has 4 divisors (see below), whose sum is σ = 126847200. Its totient is φ = 116276556.

The previous prime is 121561873. The next prime is 121561879. The reversal of 121561877 is 778165121.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 121561877 - 2² = 121561873 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 121561877.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121561873) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2642627 + ... + 2642672.

It is an arithmetic number, because the mean of its divisors is an integer number (31711800).

Almost surely, 2^121561877 is an apocalyptic number.

It is an amenable number.

121561877 is a deficient number, since it is larger than the sum of its proper divisors (5285323).

121561877 is an equidigital number, since it uses as much as digits as its factorization.

121561877 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5285322.

The product of its digits is 23520, while the sum is 38.

The square root of 121561877 is about 11025.5102829756. The cubic root of 121561877 is about 495.3731526339.

The spelling of 121561877 in words is "one hundred twenty-one million, five hundred sixty-one thousand, eight hundred seventy-seven".