21571896 has 32 divisors (see below), whose sum is σ = 55186560. Its totient is φ = 7023072.

The previous prime is 21571867. The next prime is 21571903. The reversal of 21571896 is 69817512.

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, 9420 + ... + 11483.

It is an arithmetic number, because the mean of its divisors is an integer number (1724580).

Almost surely, 2^21571896 is an apocalyptic number.

It is an amenable number.

21571896 is an abundant number, since it is smaller than the sum of its proper divisors (33614664).

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

21571896 is a wasteful number, since it uses less digits than its factorization.

21571896 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20955 (or 20951 counting only the distinct ones).

The product of its digits is 30240, while the sum is 39.

The square root of 21571896 is about 4644.5555223293. Note that the first 4 decimals coincide. The cubic root of 21571896 is about 278.3744931381.

The spelling of 21571896 in words is "twenty-one million, five hundred seventy-one thousand, eight hundred ninety-six".