21030896 has 40 divisors (see below), whose sum is σ = 42556800. Its totient is φ = 10056960.

The previous prime is 21030881. The next prime is 21030899. The reversal of 21030896 is 69803012.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21030899) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 53870 + ... + 54258.

It is an arithmetic number, because the mean of its divisors is an integer number (1063920).

Almost surely, 2^21030896 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21030896, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21278400).

21030896 is an abundant number, since it is smaller than the sum of its proper divisors (21525904).

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

21030896 is a wasteful number, since it uses less digits than its factorization.

21030896 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 537 (or 531 counting only the distinct ones).

The product of its (nonzero) digits is 2592, while the sum is 29.

The square root of 21030896 is about 4585.9454859385. The cubic root of 21030896 is about 276.0276524839.

The spelling of 21030896 in words is "twenty-one million, thirty thousand, eight hundred ninety-six".