121755721241 has 32 divisors (see below), whose sum is σ = 156746244096. Its totient is φ = 91784736000.

The previous prime is 121755721229. The next prime is 121755721247. The reversal of 121755721241 is 142127557121.

It is a cyclic number.

It is not a de Polignac number, because 121755721241 - 2³⁰ = 120681979417 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 121755721195 and 121755721204.

It is not an unprimeable number, because it can be changed into a prime (121755721247) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 10045601 + ... + 10057713.

It is an arithmetic number, because the mean of its divisors is an integer number (4898320128).

Almost surely, 2^121755721241 is an apocalyptic number.

121755721241 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

121755721241 is a deficient number, since it is larger than the sum of its proper divisors (34990522855).

121755721241 is a wasteful number, since it uses less digits than its factorization.

121755721241 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16373.

The product of its digits is 39200, while the sum is 38.

The spelling of 121755721241 in words is "one hundred twenty-one billion, seven hundred fifty-five million, seven hundred twenty-one thousand, two hundred forty-one".