220121454292921 has 2 divisors, whose sum is σ = 220121454292922. Its totient is φ = 220121454292920.

The previous prime is 220121454292849. The next prime is 220121454292973. The reversal of 220121454292921 is 129292454121022.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 118872377985321 + 101249076307600 = 10902861^2 + 10062260^2 .

It is a cyclic number.

It is not a de Polignac number, because 220121454292921 - 2¹⁹ = 220121453768633 is a prime.

It is not a weakly prime, because it can be changed into another prime (220121454202921) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110060727146460 + 110060727146461.

It is an arithmetic number, because the mean of its divisors is an integer number (110060727146461).

Almost surely, 2^{220121454292921} is an apocalyptic number.

It is an amenable number.

220121454292921 is a deficient number, since it is larger than the sum of its proper divisors (1).

220121454292921 is an equidigital number, since it uses as much as digits as its factorization.

220121454292921 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 414720, while the sum is 46.

The spelling of 220121454292921 in words is "two hundred twenty trillion, one hundred twenty-one billion, four hundred fifty-four million, two hundred ninety-two thousand, nine hundred twenty-one".