21507531773263 has 16 divisors (see below), whose sum is σ = 22915133928000. Its totient is φ = 20185995722496.

The previous prime is 21507531773159. The next prime is 21507531773311. The reversal of 21507531773263 is 36237713570512.

It is a de Polignac number, because none of the positive numbers 2^k-21507531773263 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21507531773263.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21507531773363) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4333278 + ... + 7860811.

It is an arithmetic number, because the mean of its divisors is an integer number (1432195870500).

Almost surely, 2^{21507531773263} is an apocalyptic number.

21507531773263 is a deficient number, since it is larger than the sum of its proper divisors (1407602154737).

21507531773263 is an equidigital number, since it uses as much as digits as its factorization.

21507531773263 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12194499 (or 12194465 counting only the distinct ones).

The product of its (nonzero) digits is 5556600, while the sum is 52.

The spelling of 21507531773263 in words is "twenty-one trillion, five hundred seven billion, five hundred thirty-one million, seven hundred seventy-three thousand, two hundred sixty-three".