21447722 has 32 divisors (see below), whose sum is σ = 34712064. Its totient is φ = 9921600.

The previous prime is 21447719. The next prime is 21447743. The reversal of 21447722 is 22774412.

It is a Smith number, since the sum of its digits (29) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 200393 + ... + 200499.

It is an arithmetic number, because the mean of its divisors is an integer number (1084752).

Almost surely, 2^21447722 is an apocalyptic number.

21447722 is a deficient number, since it is larger than the sum of its proper divisors (13264342).

21447722 is a wasteful number, since it uses less digits than its factorization.

21447722 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 254.

The product of its digits is 6272, while the sum is 29.

The square root of 21447722 is about 4631.1685350460. The cubic root of 21447722 is about 277.8393305847.

The spelling of 21447722 in words is "twenty-one million, four hundred forty-seven thousand, seven hundred twenty-two".