21497896 has 16 divisors (see below), whose sum is σ = 46067040. Its totient is φ = 9213360.

The previous prime is 21497881. The next prime is 21497897. The reversal of 21497896 is 69879412.

It is not an unprimeable number, because it can be changed into a prime (21497897) 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, 191890 + ... + 192001.

It is an arithmetic number, because the mean of its divisors is an integer number (2879190).

Almost surely, 2^21497896 is an apocalyptic number.

It is an amenable number.

21497896 is an abundant number, since it is smaller than the sum of its proper divisors (24569144).

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

21497896 is a wasteful number, since it uses less digits than its factorization.

21497896 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 383904 (or 383900 counting only the distinct ones).

The product of its digits is 217728, while the sum is 46.

The square root of 21497896 is about 4636.5823620421. The cubic root of 21497896 is about 278.0558175104.

The spelling of 21497896 in words is "twenty-one million, four hundred ninety-seven thousand, eight hundred ninety-six".