21887000 has 64 divisors (see below), whose sum is σ = 52509600. Its totient is φ = 8534400.

The previous prime is 21886999. The next prime is 21887081. The reversal of 21887000 is 78812.

It is a super-3 number, since 3×21887000³ (a number of 23 digits) contains 333 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 42746 + ... + 43254.

Almost surely, 2^21887000 is an apocalyptic number.

21887000 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21887000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26254800).

21887000 is an abundant number, since it is smaller than the sum of its proper divisors (30622600).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21887000 is a wasteful number, since it uses less digits than its factorization.

21887000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 573 (or 559 counting only the distinct ones).

The product of its (nonzero) digits is 896, while the sum is 26.

The square root of 21887000 is about 4678.3544115426. The cubic root of 21887000 is about 279.7233662378.

The spelling of 21887000 in words is "twenty-one million, eight hundred eighty-seven thousand".