21957226 has 16 divisors (see below), whose sum is σ = 34556544. Its totient is φ = 10443664.

The previous prime is 21957209. The next prime is 21957253. The reversal of 21957226 is 62275912.

It is a junction number, because it is equal to n+sod(n) for n = 21957191 and 21957200.

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, 7851 + ... + 10273.

It is an arithmetic number, because the mean of its divisors is an integer number (2159784).

Almost surely, 2^21957226 is an apocalyptic number.

21957226 is a deficient number, since it is larger than the sum of its proper divisors (12599318).

21957226 is a wasteful number, since it uses less digits than its factorization.

21957226 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2645.

The product of its digits is 15120, while the sum is 34.

The square root of 21957226 is about 4685.8538176089. The cubic root of 21957226 is about 280.0222176248.

The spelling of 21957226 in words is "twenty-one million, nine hundred fifty-seven thousand, two hundred twenty-six".