21300879637 has 2 divisors, whose sum is σ = 21300879638. Its totient is φ = 21300879636.

The previous prime is 21300879629. The next prime is 21300879641. The reversal of 21300879637 is 73697800312.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 14893517521 + 6407362116 = 122039^2 + 80046^2 .

It is a cyclic number.

It is not a de Polignac number, because 21300879637 - 2³ = 21300879629 is a prime.

It is a super-2 number, since 2×21300879637² (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 (21300879037) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10650439818 + 10650439819.

It is an arithmetic number, because the mean of its divisors is an integer number (10650439819).

Almost surely, 2^21300879637 is an apocalyptic number.

It is an amenable number.

21300879637 is a deficient number, since it is larger than the sum of its proper divisors (1).

21300879637 is an equidigital number, since it uses as much as digits as its factorization.

21300879637 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 381024, while the sum is 46.

The spelling of 21300879637 in words is "twenty-one billion, three hundred million, eight hundred seventy-nine thousand, six hundred thirty-seven".