21753366329 has 2 divisors, whose sum is σ = 21753366330. Its totient is φ = 21753366328.

The previous prime is 21753366317. The next prime is 21753366337. The reversal of 21753366329 is 92366335712.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18954956329 + 2798410000 = 137677^2 + 52900^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21753366329 is a prime.

It is not a weakly prime, because it can be changed into another prime (21753366629) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10876683164 + 10876683165.

It is an arithmetic number, because the mean of its divisors is an integer number (10876683165).

Almost surely, 2^21753366329 is an apocalyptic number.

It is an amenable number.

21753366329 is a deficient number, since it is larger than the sum of its proper divisors (1).

21753366329 is an equidigital number, since it uses as much as digits as its factorization.

21753366329 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1224720, while the sum is 47.

The spelling of 21753366329 in words is "twenty-one billion, seven hundred fifty-three million, three hundred sixty-six thousand, three hundred twenty-nine".