21485760 has 56 divisors (see below), whose sum is σ = 68220336. Its totient is φ = 5729280.

The previous prime is 21485747. The next prime is 21485771. The reversal of 21485760 is 6758412.

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 7 ways as a sum of consecutive naturals, for example, 10231 + ... + 12150.

Almost surely, 2^21485760 is an apocalyptic number.

21485760 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21485760 is an abundant number, since it is smaller than the sum of its proper divisors (46734576).

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

21485760 is a wasteful number, since it uses less digits than its factorization.

21485760 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22401 (or 22391 counting only the distinct ones).

The product of its (nonzero) digits is 13440, while the sum is 33.

The square root of 21485760 is about 4635.2734547166. The cubic root of 21485760 is about 278.0034849381.

The spelling of 21485760 in words is "twenty-one million, four hundred eighty-five thousand, seven hundred sixty".