21268426 has 8 divisors (see below), whose sum is σ = 33002820. Its totient is φ = 10267488.

The previous prime is 21268421. The next prime is 21268427. The reversal of 21268426 is 62486212.

It can be written as a sum of positive squares in 2 ways, for example, as 21169201 + 99225 = 4601^2 + 315^2 .

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

It is not an unprimeable number, because it can be changed into a prime (21268421) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 183291 + ... + 183406.

Almost surely, 2^21268426 is an apocalyptic number.

21268426 is a deficient number, since it is larger than the sum of its proper divisors (11734394).

21268426 is a wasteful number, since it uses less digits than its factorization.

21268426 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 366728.

The product of its digits is 9216, while the sum is 31.

The square root of 21268426 is about 4611.7703758969. The cubic root of 21268426 is about 277.0629475470.

The spelling of 21268426 in words is "twenty-one million, two hundred sixty-eight thousand, four hundred twenty-six".