21013276689637 has 2 divisors, whose sum is σ = 21013276689638. Its totient is φ = 21013276689636.

The previous prime is 21013276689617. The next prime is 21013276689661. The reversal of 21013276689637 is 73698667231012.

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., 21010910742756 + 2365946881 = 4583766^2 + 48641^2 .

It is a cyclic number.

It is not a de Polignac number, because 21013276689637 - 2²³ = 21013268301029 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21013276689617) 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, 10506638344818 + 10506638344819.

It is an arithmetic number, because the mean of its divisors is an integer number (10506638344819).

Almost surely, 2^{21013276689637} is an apocalyptic number.

It is an amenable number.

21013276689637 is a deficient number, since it is larger than the sum of its proper divisors (1).

21013276689637 is an equidigital number, since it uses as much as digits as its factorization.

21013276689637 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 27433728, while the sum is 61.

The spelling of 21013276689637 in words is "twenty-one trillion, thirteen billion, two hundred seventy-six million, six hundred eighty-nine thousand, six hundred thirty-seven".