21885387 has 8 divisors (see below), whose sum is σ = 29469840. Its totient is φ = 14445600.

The previous prime is 21885373. The next prime is 21885407. The reversal of 21885387 is 78358812.

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 21885387 - 2⁴ = 21885371 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21885317) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 35812 + ... + 36417.

It is an arithmetic number, because the mean of its divisors is an integer number (3683730).

Almost surely, 2^21885387 is an apocalyptic number.

21885387 is a deficient number, since it is larger than the sum of its proper divisors (7584453).

21885387 is a wasteful number, since it uses less digits than its factorization.

21885387 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 72333.

The product of its digits is 107520, while the sum is 42.

The square root of 21885387 is about 4678.1820186906. The cubic root of 21885387 is about 279.7164945046.

The spelling of 21885387 in words is "twenty-one million, eight hundred eighty-five thousand, three hundred eighty-seven".