21440608 has 24 divisors (see below), whose sum is σ = 48241872. Its totient is φ = 9188736.

The previous prime is 21440597. The next prime is 21440609. The reversal of 21440608 is 80604412.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21440609) 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, 47635 + ... + 48082.

It is an arithmetic number, because the mean of its divisors is an integer number (2010078).

Almost surely, 2^21440608 is an apocalyptic number.

21440608 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

21440608 is an abundant number, since it is smaller than the sum of its proper divisors (26801264).

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

21440608 is an equidigital number, since it uses as much as digits as its factorization.

21440608 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 95734 (or 95726 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 25.

The square root of 21440608 is about 4630.4004146510. The cubic root of 21440608 is about 277.8086083232.

The spelling of 21440608 in words is "twenty-one million, four hundred forty thousand, six hundred eight".