21726084529 has 2 divisors, whose sum is σ = 21726084530. Its totient is φ = 21726084528.

The previous prime is 21726084517. The next prime is 21726084563. The reversal of 21726084529 is 92548062712.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17357535504 + 4368549025 = 131748^2 + 66095^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21726084529 is a prime.

It is a super-2 number, since 2×21726084529² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (21726084229) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10863042264 + 10863042265.

It is an arithmetic number, because the mean of its divisors is an integer number (10863042265).

Almost surely, 2^21726084529 is an apocalyptic number.

It is an amenable number.

21726084529 is a deficient number, since it is larger than the sum of its proper divisors (1).

21726084529 is an equidigital number, since it uses as much as digits as its factorization.

21726084529 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 483840, while the sum is 46.

The spelling of 21726084529 in words is "twenty-one billion, seven hundred twenty-six million, eighty-four thousand, five hundred twenty-nine".