21325664127637 has 2 divisors, whose sum is σ = 21325664127638. Its totient is φ = 21325664127636.

The previous prime is 21325664127601. The next prime is 21325664127673. The reversal of 21325664127637 is 73672146652312.

Together with next prime (21325664127673) it forms an Ormiston pair, because they use the same digits, order apart.

It is a balanced prime because it is at equal distance from previous prime (21325664127601) and next prime (21325664127673).

It can be written as a sum of positive squares in only one way, i.e., 14318345713681 + 7007318413956 = 3783959^2 + 2647134^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21325664127637 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21325664127137) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10662832063818 + 10662832063819.

It is an arithmetic number, because the mean of its divisors is an integer number (10662832063819).

Almost surely, 2^{21325664127637} is an apocalyptic number.

It is an amenable number.

21325664127637 is a deficient number, since it is larger than the sum of its proper divisors (1).

21325664127637 is an equidigital number, since it uses as much as digits as its factorization.

21325664127637 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 15240960, while the sum is 55.

The spelling of 21325664127637 in words is "twenty-one trillion, three hundred twenty-five billion, six hundred sixty-four million, one hundred twenty-seven thousand, six hundred thirty-seven".