21219456 has 32 divisors (see below), whose sum is σ = 56365200. Its totient is φ = 7073024.

The previous prime is 21219449. The next prime is 21219481. The reversal of 21219456 is 65491212.

It is a tau number, because it is divible by the number of its divisors (32).

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 27246 + ... + 28013.

Almost surely, 2^21219456 is an apocalyptic number.

It is an amenable number.

21219456 is an abundant number, since it is smaller than the sum of its proper divisors (35145744).

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

21219456 is an equidigital number, since it uses as much as digits as its factorization.

21219456 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 55276 (or 55264 counting only the distinct ones).

The product of its digits is 4320, while the sum is 30.

The square root of 21219456 is about 4606.4580753546. The cubic root of 21219456 is about 276.8501407157.

The spelling of 21219456 in words is "twenty-one million, two hundred nineteen thousand, four hundred fifty-six".