21616401522673 has 2 divisors, whose sum is σ = 21616401522674. Its totient is φ = 21616401522672.

The previous prime is 21616401522533. The next prime is 21616401522679. The reversal of 21616401522673 is 37622510461612.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 12064667336929 + 9551734185744 = 3473423^2 + 3090588^2 .

It is a cyclic number.

It is not a de Polignac number, because 21616401522673 - 2³⁷ = 21478962569201 is a prime.

It is not a weakly prime, because it can be changed into another prime (21616401522679) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10808200761336 + 10808200761337.

It is an arithmetic number, because the mean of its divisors is an integer number (10808200761337).

Almost surely, 2^{21616401522673} is an apocalyptic number.

It is an amenable number.

21616401522673 is a deficient number, since it is larger than the sum of its proper divisors (1).

21616401522673 is an equidigital number, since it uses as much as digits as its factorization.

21616401522673 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 725760, while the sum is 46.

The spelling of 21616401522673 in words is "twenty-one trillion, six hundred sixteen billion, four hundred one million, five hundred twenty-two thousand, six hundred seventy-three".