21246551263 has 12 divisors (see below), whose sum is σ = 24762662760. Its totient is φ = 18176486832.

The previous prime is 21246551219. The next prime is 21246551309. The reversal of 21246551263 is 36215564212.

It is a de Polignac number, because none of the positive numbers 2^k-21246551263 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 (21246557263) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 388908 + ... + 440161.

It is an arithmetic number, because the mean of its divisors is an integer number (2063555230).

Almost surely, 2^21246551263 is an apocalyptic number.

21246551263 is a deficient number, since it is larger than the sum of its proper divisors (3516111497).

21246551263 is an equidigital number, since it uses as much as digits as its factorization.

21246551263 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 829606 (or 829599 counting only the distinct ones).

The product of its digits is 86400, while the sum is 37.

The spelling of 21246551263 in words is "twenty-one billion, two hundred forty-six million, five hundred fifty-one thousand, two hundred sixty-three".