21244738 has 8 divisors (see below), whose sum is σ = 32058432. Its totient is φ = 10558596.

The previous prime is 21244723. The next prime is 21244757. The reversal of 21244738 is 83744212.

It is a sphenic number, since it is the product of 3 distinct primes.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 31470 + ... + 32137.

It is an arithmetic number, because the mean of its divisors is an integer number (4007304).

Almost surely, 2^21244738 is an apocalyptic number.

21244738 is a deficient number, since it is larger than the sum of its proper divisors (10813694).

21244738 is a wasteful number, since it uses less digits than its factorization.

21244738 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 63776.

The product of its digits is 10752, while the sum is 31.

The square root of 21244738 is about 4609.2014492751. The cubic root of 21244738 is about 276.9600484549.

The spelling of 21244738 in words is "twenty-one million, two hundred forty-four thousand, seven hundred thirty-eight".