21064087441 has 2 divisors, whose sum is σ = 21064087442. Its totient is φ = 21064087440.

The previous prime is 21064087411. The next prime is 21064087511. The reversal of 21064087441 is 14478046012.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 14447078416 + 6617009025 = 120196^2 + 81345^2 .

It is a cyclic number.

It is not a de Polignac number, because 21064087441 - 2²¹ = 21061990289 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21064087441.

It is not a weakly prime, because it can be changed into another prime (21064087411) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10532043720 + 10532043721.

It is an arithmetic number, because the mean of its divisors is an integer number (10532043721).

Almost surely, 2^21064087441 is an apocalyptic number.

It is an amenable number.

21064087441 is a deficient number, since it is larger than the sum of its proper divisors (1).

21064087441 is an equidigital number, since it uses as much as digits as its factorization.

21064087441 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 43008, while the sum is 37.

The spelling of 21064087441 in words is "twenty-one billion, sixty-four million, eighty-seven thousand, four hundred forty-one".