21753810863 has 4 divisors (see below), whose sum is σ = 21813085920. Its totient is φ = 21694535808.

The previous prime is 21753810851. The next prime is 21753810889. The reversal of 21753810863 is 36801835712.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 21753810863 - 2²⁰ = 21752762287 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 (21753810893) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 29636978 + ... + 29637711.

It is an arithmetic number, because the mean of its divisors is an integer number (5453271480).

Almost surely, 2^21753810863 is an apocalyptic number.

21753810863 is a deficient number, since it is larger than the sum of its proper divisors (59275057).

21753810863 is an equidigital number, since it uses as much as digits as its factorization.

21753810863 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 59275056.

The product of its (nonzero) digits is 241920, while the sum is 44.

The spelling of 21753810863 in words is "twenty-one billion, seven hundred fifty-three million, eight hundred ten thousand, eight hundred sixty-three".