20868305 has 8 divisors (see below), whose sum is σ = 25107432. Its totient is φ = 16651008.

The previous prime is 20868293. The next prime is 20868319. The reversal of 20868305 is 50386802.

It can be written as a sum of positive squares in 4 ways, for example, as 10816 + 20857489 = 104^2 + 4567^2 .

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 20868305 - 2¹⁰ = 20867281 is a prime.

It is a Duffinian 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, 3272 + ... + 7241.

It is an arithmetic number, because the mean of its divisors is an integer number (3138429).

Almost surely, 2^20868305 is an apocalyptic number.

It is an amenable number.

20868305 is a deficient number, since it is larger than the sum of its proper divisors (4239127).

20868305 is a wasteful number, since it uses less digits than its factorization.

20868305 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10915.

The product of its (nonzero) digits is 11520, while the sum is 32.

The square root of 20868305 is about 4568.1839936675. The cubic root of 20868305 is about 275.3144832029.

The spelling of 20868305 in words is "twenty million, eight hundred sixty-eight thousand, three hundred five".