21300021461 has 2 divisors, whose sum is σ = 21300021462. Its totient is φ = 21300021460.

The previous prime is 21300021451. The next prime is 21300021499. The reversal of 21300021461 is 16412000312.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 13393432900 + 7906588561 = 115730^2 + 88919^2 .

It is a cyclic number.

It is not a de Polignac number, because 21300021461 - 2¹⁰ = 21300020437 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21300021451) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10650010730 + 10650010731.

It is an arithmetic number, because the mean of its divisors is an integer number (10650010731).

Almost surely, 2^21300021461 is an apocalyptic number.

It is an amenable number.

21300021461 is a deficient number, since it is larger than the sum of its proper divisors (1).

21300021461 is an equidigital number, since it uses as much as digits as its factorization.

21300021461 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 288, while the sum is 20.

Adding to 21300021461 its reverse (16412000312), we get a palindrome (37712021773).

The spelling of 21300021461 in words is "twenty-one billion, three hundred million, twenty-one thousand, four hundred sixty-one".