21827216 has 10 divisors (see below), whose sum is σ = 42290262. Its totient is φ = 10913600.

The previous prime is 21827191. The next prime is 21827233. The reversal of 21827216 is 61272812.

It can be written as a sum of positive squares in only one way, i.e., 11587216 + 10240000 = 3404^2 + 3200^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 682085 + ... + 682116.

Almost surely, 2^21827216 is an apocalyptic number.

It is an amenable number.

21827216 is a deficient number, since it is larger than the sum of its proper divisors (20463046).

21827216 is a wasteful number, since it uses less digits than its factorization.

21827216 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1364209 (or 1364203 counting only the distinct ones).

The product of its digits is 2688, while the sum is 29.

The square root of 21827216 is about 4671.9606162724. The cubic root of 21827216 is about 279.4684473200.

The spelling of 21827216 in words is "twenty-one million, eight hundred twenty-seven thousand, two hundred sixteen".