21456446 has 12 divisors (see below), whose sum is σ = 35376936. Its totient is φ = 9752820.

The previous prime is 21456439. The next prime is 21456469. The reversal of 21456446 is 64465412.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 44090 + ... + 44573.

It is an arithmetic number, because the mean of its divisors is an integer number (2948078).

Almost surely, 2^21456446 is an apocalyptic number.

21456446 is a deficient number, since it is larger than the sum of its proper divisors (13920490).

21456446 is a wasteful number, since it uses less digits than its factorization.

21456446 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 88687 (or 88676 counting only the distinct ones).

The product of its digits is 23040, while the sum is 32.

The square root of 21456446 is about 4632.1103182027. The cubic root of 21456446 is about 277.8769964613.

The spelling of 21456446 in words is "twenty-one million, four hundred fifty-six thousand, four hundred forty-six".