21306470573 has 2 divisors, whose sum is σ = 21306470574. Its totient is φ = 21306470572.

The previous prime is 21306470569. The next prime is 21306470621. The reversal of 21306470573 is 37507460312.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 21204601924 + 101868649 = 145618^2 + 10093^2 .

It is a cyclic number.

It is not a de Polignac number, because 21306470573 - 2² = 21306470569 is a prime.

It is a super-2 number, since 2×21306470573² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21306475573) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10653235286 + 10653235287.

It is an arithmetic number, because the mean of its divisors is an integer number (10653235287).

Almost surely, 2^21306470573 is an apocalyptic number.

It is an amenable number.

21306470573 is a deficient number, since it is larger than the sum of its proper divisors (1).

21306470573 is an equidigital number, since it uses as much as digits as its factorization.

21306470573 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 105840, while the sum is 38.

The spelling of 21306470573 in words is "twenty-one billion, three hundred six million, four hundred seventy thousand, five hundred seventy-three".