21888559 has 8 divisors (see below), whose sum is σ = 27289728. Its totient is φ = 17055960.

The previous prime is 21888557. The next prime is 21888563. The reversal of 21888559 is 95588812.

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 21888559 - 2¹ = 21888557 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 (21888553) 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 7 ways as a sum of consecutive naturals, for example, 142057 + ... + 142210.

It is an arithmetic number, because the mean of its divisors is an integer number (3411216).

Almost surely, 2^21888559 is an apocalyptic number.

21888559 is a deficient number, since it is larger than the sum of its proper divisors (5401169).

21888559 is a wasteful number, since it uses less digits than its factorization.

21888559 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 284285.

The product of its digits is 230400, while the sum is 46.

The square root of 21888559 is about 4678.5210269913. The cubic root of 21888559 is about 279.7300075983.

The spelling of 21888559 in words is "twenty-one million, eight hundred eighty-eight thousand, five hundred fifty-nine".