21273307 has 8 divisors (see below), whose sum is σ = 24572592. Its totient is φ = 18201600.

The previous prime is 21273289. The next prime is 21273319. The reversal of 21273307 is 70337212.

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 21273307 - 2¹¹ = 21271259 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21273107) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 56694 + ... + 57067.

It is an arithmetic number, because the mean of its divisors is an integer number (3071574).

Almost surely, 2^21273307 is an apocalyptic number.

21273307 is a deficient number, since it is larger than the sum of its proper divisors (3299285).

21273307 is a wasteful number, since it uses less digits than its factorization.

21273307 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 113789.

The product of its (nonzero) digits is 1764, while the sum is 25.

The square root of 21273307 is about 4612.2995349392. The cubic root of 21273307 is about 277.0841407907.

The spelling of 21273307 in words is "twenty-one million, two hundred seventy-three thousand, three hundred seven".