21852668291 has 4 divisors (see below), whose sum is σ = 21857478792. Its totient is φ = 21847857792.

The previous prime is 21852668263. The next prime is 21852668293. The reversal of 21852668291 is 19286625812.

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 21852668291 - 2²² = 21848473987 is a prime.

It is a super-2 number, since 2×21852668291² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21852668293) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2398430 + ... + 2407523.

It is an arithmetic number, because the mean of its divisors is an integer number (5464369698).

Almost surely, 2^21852668291 is an apocalyptic number.

21852668291 is a deficient number, since it is larger than the sum of its proper divisors (4810501).

21852668291 is an equidigital number, since it uses as much as digits as its factorization.

21852668291 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4810500.

The product of its digits is 829440, while the sum is 50.

The spelling of 21852668291 in words is "twenty-one billion, eight hundred fifty-two million, six hundred sixty-eight thousand, two hundred ninety-one".