21909263358997 has 16 divisors (see below), whose sum is σ = 25551197872000. Its totient is φ = 18778606751520.

The previous prime is 21909263358989. The next prime is 21909263359033. The reversal of 21909263358997 is 79985336290912.

It is not a de Polignac number, because 21909263358997 - 2³ = 21909263358989 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21909263338997) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 7253722 + ... + 9820132.

It is an arithmetic number, because the mean of its divisors is an integer number (1596949867000).

Almost surely, 2^{21909263358997} is an apocalyptic number.

It is an amenable number.

21909263358997 is a deficient number, since it is larger than the sum of its proper divisors (3641934513003).

21909263358997 is an equidigital number, since it uses as much as digits as its factorization.

21909263358997 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2591321 (or 2591307 counting only the distinct ones).

The product of its (nonzero) digits is 396809280, while the sum is 73.

The spelling of 21909263358997 in words is "twenty-one trillion, nine hundred nine billion, two hundred sixty-three million, three hundred fifty-eight thousand, nine hundred ninety-seven".