21495520 has 48 divisors (see below), whose sum is σ = 52170048. Its totient is φ = 8363520.

The previous prime is 21495503. The next prime is 21495541. The reversal of 21495520 is 2559412.

It is a congruent number.

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, 4105 + ... + 7735.

It is an arithmetic number, because the mean of its divisors is an integer number (1086876).

Almost surely, 2^21495520 is an apocalyptic number.

21495520 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 21495520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26085024).

21495520 is an abundant number, since it is smaller than the sum of its proper divisors (30674528).

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

21495520 is a wasteful number, since it uses less digits than its factorization.

21495520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3683 (or 3675 counting only the distinct ones).

The product of its (nonzero) digits is 3600, while the sum is 28.

The square root of 21495520 is about 4636.3261317556. The cubic root of 21495520 is about 278.0455733302.

The spelling of 21495520 in words is "twenty-one million, four hundred ninety-five thousand, five hundred twenty".