21223938 has 16 divisors (see below), whose sum is σ = 42869376. Its totient is φ = 7004400.

The previous prime is 21223927. The next prime is 21223957. The reversal of 21223938 is 83932212.

It is a happy number.

It is a Curzon number.

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, 16906 + ... + 18117.

It is an arithmetic number, because the mean of its divisors is an integer number (2679336).

Almost surely, 2^21223938 is an apocalyptic number.

21223938 is an abundant number, since it is smaller than the sum of its proper divisors (21645438).

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

21223938 is a wasteful number, since it uses less digits than its factorization.

21223938 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35129.

The product of its digits is 5184, while the sum is 30.

The square root of 21223938 is about 4606.9445405822. The cubic root of 21223938 is about 276.8696315543.

The spelling of 21223938 in words is "twenty-one million, two hundred twenty-three thousand, nine hundred thirty-eight".