21846240 has 192 divisors, whose sum is σ = 82555200. Its totient is φ = 5363712.

The previous prime is 21846239. The next prime is 21846271. The reversal of 21846240 is 4264812.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 55966 + ... + 56354.

It is an arithmetic number, because the mean of its divisors is an integer number (429975).

Almost surely, 2^21846240 is an apocalyptic number.

21846240 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 21846240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (41277600).

21846240 is an abundant number, since it is smaller than the sum of its proper divisors (60708960).

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

21846240 is a wasteful number, since it uses less digits than its factorization.

21846240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 426 (or 412 counting only the distinct ones).

The product of its (nonzero) digits is 3072, while the sum is 27.

The square root of 21846240 is about 4673.9961489073. The cubic root of 21846240 is about 279.5496160756.

The spelling of 21846240 in words is "twenty-one million, eight hundred forty-six thousand, two hundred forty".