21504044201 has 2 divisors, whose sum is σ = 21504044202. Its totient is φ = 21504044200.

The previous prime is 21504044183. The next prime is 21504044207. The reversal of 21504044201 is 10244040512.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 14865705625 + 6638338576 = 121925^2 + 81476^2 .

It is a cyclic number.

It is not a de Polignac number, because 21504044201 - 2⁶ = 21504044137 is a prime.

It is not a weakly prime, because it can be changed into another prime (21504044207) 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, 10752022100 + 10752022101.

It is an arithmetic number, because the mean of its divisors is an integer number (10752022101).

Almost surely, 2^21504044201 is an apocalyptic number.

It is an amenable number.

21504044201 is a deficient number, since it is larger than the sum of its proper divisors (1).

21504044201 is an equidigital number, since it uses as much as digits as its factorization.

21504044201 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1280, while the sum is 23.

Adding to 21504044201 its reverse (10244040512), we get a palindrome (31748084713).

The spelling of 21504044201 in words is "twenty-one billion, five hundred four million, forty-four thousand, two hundred one".