121561242165121 has 12 divisors (see below), whose sum is σ = 136724272377616. Its totient is φ = 107940215025720.

The previous prime is 121561242165091. The next prime is 121561242165133.

121561242165121 is nontrivially palindromic in base 10.

It is not a de Polignac number, because 121561242165121 - 2⁵ = 121561242165089 is a prime.

It is not an unprimeable number, because it can be changed into a prime (121561242165151) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 11681836251 + ... + 11681846656.

Almost surely, 2^{121561242165121} is an apocalyptic number.

121561242165121 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

121561242165121 is a deficient number, since it is larger than the sum of its proper divisors (15163030212495).

121561242165121 is a wasteful number, since it uses less digits than its factorization.

121561242165121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23363682972 (or 23363682961 counting only the distinct ones).

The product of its digits is 57600, while the sum is 40.

The spelling of 121561242165121 in words is "one hundred twenty-one trillion, five hundred sixty-one billion, two hundred forty-two million, one hundred sixty-five thousand, one hundred twenty-one".