21230021297 has 2 divisors, whose sum is σ = 21230021298. Its totient is φ = 21230021296.

The previous prime is 21230021273. The next prime is 21230021347. The reversal of 21230021297 is 79212003212.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 21157447936 + 72573361 = 145456^2 + 8519^2 .

It is a cyclic number.

It is not a de Polignac number, because 21230021297 - 2¹² = 21230017201 is a prime.

It is not a weakly prime, because it can be changed into another prime (21230020297) 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, 10615010648 + 10615010649.

It is an arithmetic number, because the mean of its divisors is an integer number (10615010649).

Almost surely, 2^21230021297 is an apocalyptic number.

It is an amenable number.

21230021297 is a deficient number, since it is larger than the sum of its proper divisors (1).

21230021297 is an equidigital number, since it uses as much as digits as its factorization.

21230021297 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3024, while the sum is 29.

The spelling of 21230021297 in words is "twenty-one billion, two hundred thirty million, twenty-one thousand, two hundred ninety-seven".