21529116 has 72 divisors (see below), whose sum is σ = 63903840. Its totient is φ = 5982336.

The previous prime is 21529093. The next prime is 21529129. The reversal of 21529116 is 61192512.

21529116 is a `hidden beast` number, since 21 + 529 + 116 = 666.

It is a self number, because there is not a number n which added to its sum of digits gives 21529116.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 8170 + ... + 10478.

Almost surely, 2^21529116 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 21529116, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31951920).

21529116 is an abundant number, since it is smaller than the sum of its proper divisors (42374724).

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

21529116 is a wasteful number, since it uses less digits than its factorization.

21529116 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2363 (or 2358 counting only the distinct ones).

The product of its digits is 1080, while the sum is 27.

The square root of 21529116 is about 4639.9478445345. The cubic root of 21529116 is about 278.1903532152.

The spelling of 21529116 in words is "twenty-one million, five hundred twenty-nine thousand, one hundred sixteen".