21604152 has 32 divisors (see below), whose sum is σ = 55472400. Its totient is φ = 7006464.

The previous prime is 21604151. The next prime is 21604169. The reversal of 21604152 is 25140612.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21604151) 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, 11277 + ... + 13052.

Almost surely, 2^21604152 is an apocalyptic number.

It is an amenable number.

21604152 is an abundant number, since it is smaller than the sum of its proper divisors (33868248).

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

21604152 is a wasteful number, since it uses less digits than its factorization.

21604152 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24375 (or 24371 counting only the distinct ones).

The product of its (nonzero) digits is 480, while the sum is 21.

The square root of 21604152 is about 4648.0266780646. The cubic root of 21604152 is about 278.5131732039.

Adding to 21604152 its reverse (25140612), we get a palindrome (46744764).

The spelling of 21604152 in words is "twenty-one million, six hundred four thousand, one hundred fifty-two".