21443511325813 has 2 divisors, whose sum is σ = 21443511325814. Its totient is φ = 21443511325812.

The previous prime is 21443511325793. The next prime is 21443511325861. The reversal of 21443511325813 is 31852311534412.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 21443401012804 + 110313009 = 4630702^2 + 10503^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21443511325813 is a prime.

It is a super-2 number, since 2×21443511325813² (a number of 27 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21443511325813.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21443511326813) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10721755662906 + 10721755662907.

It is an arithmetic number, because the mean of its divisors is an integer number (10721755662907).

Almost surely, 2^{21443511325813} is an apocalyptic number.

It is an amenable number.

21443511325813 is a deficient number, since it is larger than the sum of its proper divisors (1).

21443511325813 is an equidigital number, since it uses as much as digits as its factorization.

21443511325813 is an evil number, because the sum of its binary digits is even.

The product of its digits is 345600, while the sum is 43.

The spelling of 21443511325813 in words is "twenty-one trillion, four hundred forty-three billion, five hundred eleven million, three hundred twenty-five thousand, eight hundred thirteen".