21191896 has 32 divisors (see below), whose sum is σ = 43552080. Its totient is φ = 9587200.

The previous prime is 21191873. The next prime is 21191917. The reversal of 21191896 is 69819112.

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, 24300 + ... + 25156.

Almost surely, 2^21191896 is an apocalyptic number.

It is an amenable number.

21191896 is an abundant number, since it is smaller than the sum of its proper divisors (22360184).

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

21191896 is a wasteful number, since it uses less digits than its factorization.

21191896 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1155 (or 1151 counting only the distinct ones).

The product of its digits is 7776, while the sum is 37.

The square root of 21191896 is about 4603.4656510069. The cubic root of 21191896 is about 276.7302303913.

The spelling of 21191896 in words is "twenty-one million, one hundred ninety-one thousand, eight hundred ninety-six".