21782368 has 24 divisors (see below), whose sum is σ = 43590960. Its totient is φ = 10711680.

The previous prime is 21782363. The next prime is 21782399. The reversal of 21782368 is 86328712.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21782363) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3628 + ... + 7531.

It is an arithmetic number, because the mean of its divisors is an integer number (1816290).

Almost surely, 2^21782368 is an apocalyptic number.

It is an amenable number.

21782368 is an abundant number, since it is smaller than the sum of its proper divisors (21808592).

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

21782368 is a wasteful number, since it uses less digits than its factorization.

21782368 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11230 (or 11222 counting only the distinct ones).

The product of its digits is 32256, while the sum is 37.

The square root of 21782368 is about 4667.1584502779. The cubic root of 21782368 is about 279.2769097623.

The spelling of 21782368 in words is "twenty-one million, seven hundred eighty-two thousand, three hundred sixty-eight".