21898885 has 8 divisors (see below), whose sum is σ = 26649216. Its totient is φ = 17272080.

The previous prime is 21898861. The next prime is 21898889. The reversal of 21898885 is 58889812.

It is a happy number.

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

It is not a de Polignac number, because 21898885 - 2¹⁷ = 21767813 is a prime.

It is a super-2 number, since 2×21898885² = 959122328486450, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21898889) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 30489 + ... + 31198.

It is an arithmetic number, because the mean of its divisors is an integer number (3331152).

Almost surely, 2^21898885 is an apocalyptic number.

It is an amenable number.

21898885 is a deficient number, since it is larger than the sum of its proper divisors (4750331).

21898885 is an equidigital number, since it uses as much as digits as its factorization.

21898885 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 61763.

The product of its digits is 368640, while the sum is 49.

The square root of 21898885 is about 4679.6244507439. The cubic root of 21898885 is about 279.7739885347.

The spelling of 21898885 in words is "twenty-one million, eight hundred ninety-eight thousand, eight hundred eighty-five".