121656505373 has 16 divisors (see below), whose sum is σ = 137927462400. Its totient is φ = 106374565440.

The previous prime is 121656505349. The next prime is 121656505387. The reversal of 121656505373 is 373505656121.

It is a de Polignac number, because none of the positive numbers 2^k-121656505373 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121656505073) 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 15 ways as a sum of consecutive naturals, for example, 2305343 + ... + 2357523.

It is an arithmetic number, because the mean of its divisors is an integer number (8620466400).

Almost surely, 2^121656505373 is an apocalyptic number.

121656505373 is a gapful number since it is divisible by the number (13) formed by its first and last digit.

It is an amenable number.

121656505373 is a deficient number, since it is larger than the sum of its proper divisors (16270957027).

121656505373 is a wasteful number, since it uses less digits than its factorization.

121656505373 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 61652.

The product of its (nonzero) digits is 567000, while the sum is 44.

The spelling of 121656505373 in words is "one hundred twenty-one billion, six hundred fifty-six million, five hundred five thousand, three hundred seventy-three".