21163250523 has 4 divisors (see below), whose sum is σ = 28217667368. Its totient is φ = 14108833680.

The previous prime is 21163250483. The next prime is 21163250573. The reversal of 21163250523 is 32505236112.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 21163250523 - 2⁸ = 21163250267 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21163250573) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3527208418 + ... + 3527208423.

It is an arithmetic number, because the mean of its divisors is an integer number (7054416842).

Almost surely, 2^21163250523 is an apocalyptic number.

21163250523 is a deficient number, since it is larger than the sum of its proper divisors (7054416845).

21163250523 is an equidigital number, since it uses as much as digits as its factorization.

21163250523 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7054416844.

The product of its (nonzero) digits is 10800, while the sum is 30.

Adding to 21163250523 its reverse (32505236112), we get a palindrome (53668486635).

The spelling of 21163250523 in words is "twenty-one billion, one hundred sixty-three million, two hundred fifty thousand, five hundred twenty-three".