121556622673985 has 16 divisors (see below), whose sum is σ = 146674660401360. Its totient is φ = 96707495301120.

The previous prime is 121556622673961. The next prime is 121556622673999. The reversal of 121556622673985 is 589376226655121.

It is a Cunningham number, because it is equal to 11025272²+1.

It can be written as a sum of positive squares in 8 ways, for example, as 46131861697936 + 75424760976049 = 6792044^2 + 8684743^2 .

It is a de Polignac number, because none of the positive numbers 2^k-121556622673985 is a prime.

It is an unprimeable number.

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, 277769309 + ... + 278206581.

It is an arithmetic number, because the mean of its divisors is an integer number (9167166275085).

Almost surely, 2^{121556622673985} is an apocalyptic number.

It is an amenable number.

121556622673985 is a deficient number, since it is larger than the sum of its proper divisors (25118037727375).

121556622673985 is a wasteful number, since it uses less digits than its factorization.

121556622673985 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 744628.

The product of its digits is 326592000, while the sum is 68.

The spelling of 121556622673985 in words is "one hundred twenty-one trillion, five hundred fifty-six billion, six hundred twenty-two million, six hundred seventy-three thousand, nine hundred eighty-five".