20554091221 has 2 divisors, whose sum is σ = 20554091222. Its totient is φ = 20554091220.

The previous prime is 20554091167. The next prime is 20554091237. The reversal of 20554091221 is 12219045502.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 15989602500 + 4564488721 = 126450^2 + 67561^2 .

It is a cyclic number.

It is not a de Polignac number, because 20554091221 - 2⁹ = 20554090709 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20554091291) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10277045610 + 10277045611.

It is an arithmetic number, because the mean of its divisors is an integer number (10277045611).

Almost surely, 2^20554091221 is an apocalyptic number.

It is an amenable number.

20554091221 is a deficient number, since it is larger than the sum of its proper divisors (1).

20554091221 is an equidigital number, since it uses as much as digits as its factorization.

20554091221 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 7200, while the sum is 31.

The spelling of 20554091221 in words is "twenty billion, five hundred fifty-four million, ninety-one thousand, two hundred twenty-one".