21630042666413 has 2 divisors, whose sum is σ = 21630042666414. Its totient is φ = 21630042666412.

The previous prime is 21630042666403. The next prime is 21630042666431. The reversal of 21630042666413 is 31466624003612.

Together with next prime (21630042666431) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18762784549609 + 2867258116804 = 4331603^2 + 1693298^2 .

It is a cyclic number.

It is not a de Polignac number, because 21630042666413 - 2³⁶ = 21561323189677 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21630042666403) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10815021333206 + 10815021333207.

It is an arithmetic number, because the mean of its divisors is an integer number (10815021333207).

Almost surely, 2^{21630042666413} is an apocalyptic number.

It is an amenable number.

21630042666413 is a deficient number, since it is larger than the sum of its proper divisors (1).

21630042666413 is an equidigital number, since it uses as much as digits as its factorization.

21630042666413 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 746496, while the sum is 44.

The spelling of 21630042666413 in words is "twenty-one trillion, six hundred thirty billion, forty-two million, six hundred sixty-six thousand, four hundred thirteen".