21654600580609 has 2 divisors, whose sum is σ = 21654600580610. Its totient is φ = 21654600580608.

The previous prime is 21654600580489. The next prime is 21654600580619. The reversal of 21654600580609 is 90608500645612.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 12539955792400 + 9114644788209 = 3541180^2 + 3019047^2 .

It is a cyclic number.

It is not a de Polignac number, because 21654600580609 - 2⁹ = 21654600580097 is a prime.

It is not a weakly prime, because it can be changed into another prime (21654600580619) 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, 10827300290304 + 10827300290305.

It is an arithmetic number, because the mean of its divisors is an integer number (10827300290305).

Almost surely, 2^{21654600580609} is an apocalyptic number.

It is an amenable number.

21654600580609 is a deficient number, since it is larger than the sum of its proper divisors (1).

21654600580609 is an equidigital number, since it uses as much as digits as its factorization.

21654600580609 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3110400, while the sum is 52.

The spelling of 21654600580609 in words is "twenty-one trillion, six hundred fifty-four billion, six hundred million, five hundred eighty thousand, six hundred nine".