21488500 has 48 divisors (see below), whose sum is σ = 51210432. Its totient is φ = 7812000.

The previous prime is 21488497. The next prime is 21488513. The reversal of 21488500 is 588412.

21488500 = 450² + 451² + ... + 537².

It is a hoax number, since the sum of its digits (28) coincides with the sum of the digits of its distinct prime factors.

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, 3547 + ... + 7453.

It is an arithmetic number, because the mean of its divisors is an integer number (1066884).

Almost surely, 2^21488500 is an apocalyptic number.

21488500 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 21488500, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25605216).

21488500 is an abundant number, since it is smaller than the sum of its proper divisors (29721932).

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

21488500 is a wasteful number, since it uses less digits than its factorization.

21488500 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3937 (or 3925 counting only the distinct ones).

The product of its (nonzero) digits is 2560, while the sum is 28.

The square root of 21488500 is about 4635.5690049874. The cubic root of 21488500 is about 278.0153020233.

It can be divided in two parts, 2148 and 8500, that added together give a cube (10648 = 22³).

The spelling of 21488500 in words is "twenty-one million, four hundred eighty-eight thousand, five hundred".