21519472 has 40 divisors (see below), whose sum is σ = 45181136. Its totient is φ = 9870336.

The previous prime is 21519469. The next prime is 21519497. The reversal of 21519472 is 27491512.

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, 63688 + ... + 64024.

Almost surely, 2^21519472 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 21519472, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22590568).

21519472 is an abundant number, since it is smaller than the sum of its proper divisors (23661664).

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

21519472 is a wasteful number, since it uses less digits than its factorization.

21519472 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 665 (or 659 counting only the distinct ones).

The product of its digits is 5040, while the sum is 31.

The square root of 21519472 is about 4638.9084923072. The cubic root of 21519472 is about 278.1488084151.

The spelling of 21519472 in words is "twenty-one million, five hundred nineteen thousand, four hundred seventy-two".