21730697633 has 2 divisors, whose sum is σ = 21730697634. Its totient is φ = 21730697632.

The previous prime is 21730697567. The next prime is 21730697663. The reversal of 21730697633 is 33679603712.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20785565584 + 945132049 = 144172^2 + 30743^2 .

It is a cyclic number.

It is not a de Polignac number, because 21730697633 - 2⁸ = 21730697377 is a prime.

It is not a weakly prime, because it can be changed into another prime (21730697663) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10865348816 + 10865348817.

It is an arithmetic number, because the mean of its divisors is an integer number (10865348817).

Almost surely, 2^21730697633 is an apocalyptic number.

It is an amenable number.

21730697633 is a deficient number, since it is larger than the sum of its proper divisors (1).

21730697633 is an equidigital number, since it uses as much as digits as its factorization.

21730697633 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 857304, while the sum is 47.

The spelling of 21730697633 in words is "twenty-one billion, seven hundred thirty million, six hundred ninety-seven thousand, six hundred thirty-three".