121613055661 has 4 divisors (see below), whose sum is σ = 121613968800. Its totient is φ = 121612142524.

The previous prime is 121613055623. The next prime is 121613055667. The reversal of 121613055661 is 166550316121.

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, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 121613055661 - 2²¹ = 121610958509 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 121613055661.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121613055667) 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, 213751 + ... + 537508.

It is an arithmetic number, because the mean of its divisors is an integer number (30403492200).

Almost surely, 2^121613055661 is an apocalyptic number.

It is an amenable number.

121613055661 is a deficient number, since it is larger than the sum of its proper divisors (913139).

121613055661 is an equidigital number, since it uses as much as digits as its factorization.

121613055661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 913138.

The product of its (nonzero) digits is 32400, while the sum is 37.

The spelling of 121613055661 in words is "one hundred twenty-one billion, six hundred thirteen million, fifty-five thousand, six hundred sixty-one".