21268351 has 8 divisors (see below), whose sum is σ = 22992704. Its totient is φ = 19556640.

The previous prime is 21268327. The next prime is 21268361. The reversal of 21268351 is 15386212.

21268351 = 134² + 135² + ... + 404².

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

It is a cyclic number.

It is not a de Polignac number, because 21268351 - 2⁹ = 21267839 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21268361) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 505 + ... + 6541.

It is an arithmetic number, because the mean of its divisors is an integer number (2874088).

Almost surely, 2^21268351 is an apocalyptic number.

21268351 is a deficient number, since it is larger than the sum of its proper divisors (1724353).

21268351 is a wasteful number, since it uses less digits than its factorization.

21268351 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6321.

The product of its digits is 2880, while the sum is 28.

The square root of 21268351 is about 4611.7622445222. The cubic root of 21268351 is about 277.0626218726.

The spelling of 21268351 in words is "twenty-one million, two hundred sixty-eight thousand, three hundred fifty-one".