21595040 has 48 divisors (see below), whose sum is σ = 51438240. Its totient is φ = 8567040.

The previous prime is 21595031. The next prime is 21595081. The reversal of 21595040 is 4059512.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 21755 + ... + 22725.

It is an arithmetic number, because the mean of its divisors is an integer number (1071630).

Almost surely, 2^21595040 is an apocalyptic number.

21595040 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 21595040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25719120).

21595040 is an abundant number, since it is smaller than the sum of its proper divisors (29843200).

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

21595040 is a wasteful number, since it uses less digits than its factorization.

21595040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1125 (or 1117 counting only the distinct ones).

The product of its (nonzero) digits is 1800, while the sum is 26.

The square root of 21595040 is about 4647.0463737733. The cubic root of 21595040 is about 278.4740114584.

The spelling of 21595040 in words is "twenty-one million, five hundred ninety-five thousand, forty".