21538896 has 20 divisors (see below), whose sum is σ = 55642272. Its totient is φ = 7179616.

The previous prime is 21538883. The next prime is 21538897. The reversal of 21538896 is 69883512.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21538897) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 224316 + ... + 224411.

Almost surely, 2^21538896 is an apocalyptic number.

It is an amenable number.

21538896 is an abundant number, since it is smaller than the sum of its proper divisors (34103376).

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

21538896 is a wasteful number, since it uses less digits than its factorization.

21538896 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 448738 (or 448732 counting only the distinct ones).

The product of its digits is 103680, while the sum is 42.

The square root of 21538896 is about 4641.0016160307. The cubic root of 21538896 is about 278.2324712130.

The spelling of 21538896 in words is "twenty-one million, five hundred thirty-eight thousand, eight hundred ninety-six".