21630083621 has 2 divisors, whose sum is σ = 21630083622. Its totient is φ = 21630083620.

The previous prime is 21630083617. The next prime is 21630083627. The reversal of 21630083621 is 12638003612.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17196388225 + 4433695396 = 131135^2 + 66586^2 .

It is a cyclic number.

It is not a de Polignac number, because 21630083621 - 2² = 21630083617 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21630083627) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10815041810 + 10815041811.

It is an arithmetic number, because the mean of its divisors is an integer number (10815041811).

Almost surely, 2^21630083621 is an apocalyptic number.

It is an amenable number.

21630083621 is a deficient number, since it is larger than the sum of its proper divisors (1).

21630083621 is an equidigital number, since it uses as much as digits as its factorization.

21630083621 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 10368, while the sum is 32.

The spelling of 21630083621 in words is "twenty-one billion, six hundred thirty million, eighty-three thousand, six hundred twenty-one".