21860544 has 56 divisors (see below), whose sum is σ = 59271408. Its totient is φ = 7106560.

The previous prime is 21860543. The next prime is 21860561. The reversal of 21860544 is 44506812.

It is not an unprimeable number, because it can be changed into a prime (21860543) 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, 6484 + ... + 9260.

It is an arithmetic number, because the mean of its divisors is an integer number (1058418).

Almost surely, 2^21860544 is an apocalyptic number.

21860544 is a gapful number since it is divisible by the number (24) 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 21860544, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29635704).

21860544 is an abundant number, since it is smaller than the sum of its proper divisors (37410864).

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

21860544 is a wasteful number, since it uses less digits than its factorization.

21860544 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2833 (or 2823 counting only the distinct ones).

The product of its (nonzero) digits is 7680, while the sum is 30.

The square root of 21860544 is about 4675.5260666582. The cubic root of 21860544 is about 279.6106152118.

The spelling of 21860544 in words is "twenty-one million, eight hundred sixty thousand, five hundred forty-four".