21859488 has 108 divisors (see below), whose sum is σ = 72358650. Its totient is φ = 6241536.

The previous prime is 21859483. The next prime is 21859507. The reversal of 21859488 is 88495812.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 19820304 + 2039184 = 4452^2 + 1428^2 .

It is not an unprimeable number, because it can be changed into a prime (21859483) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 13338 + ... + 14886.

Almost surely, 2^21859488 is an apocalyptic number.

21859488 is a gapful number since it is divisible by the number (28) 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 21859488, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36179325).

21859488 is an abundant number, since it is smaller than the sum of its proper divisors (50499162).

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

21859488 is a wasteful number, since it uses less digits than its factorization.

21859488 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1579 (or 1561 counting only the distinct ones).

The product of its digits is 184320, while the sum is 45.

The square root of 21859488 is about 4675.4131368255. The cubic root of 21859488 is about 279.6061128297.

The spelling of 21859488 in words is "twenty-one million, eight hundred fifty-nine thousand, four hundred eighty-eight".