21968855 has 8 divisors (see below), whose sum is σ = 26680752. Its totient is φ = 17363008.

The previous prime is 21968819. The next prime is 21968867. The reversal of 21968855 is 55886912.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21968855 - 2¹⁶ = 21903319 is a prime.

It is a super-2 number, since 2×21968855² = 965261180022050, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 26054 + ... + 26883.

It is an arithmetic number, because the mean of its divisors is an integer number (3335094).

Almost surely, 2^21968855 is an apocalyptic number.

21968855 is a deficient number, since it is larger than the sum of its proper divisors (4711897).

21968855 is an equidigital number, since it uses as much as digits as its factorization.

21968855 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 53025.

The product of its digits is 172800, while the sum is 44.

The square root of 21968855 is about 4687.0945157955. The cubic root of 21968855 is about 280.0716440817.

The spelling of 21968855 in words is "twenty-one million, nine hundred sixty-eight thousand, eight hundred fifty-five".