268187309 has 4 divisors (see below), whose sum is σ = 288817116. Its totient is φ = 247557504.

The previous prime is 268187281. The next prime is 268187317. The reversal of 268187309 is 903781862.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 84584809 + 183602500 = 9197^2 + 13550^2 .

It is a cyclic number.

It is not a de Polignac number, because 268187309 - 2²⁰ = 267138733 is a prime.

It is a super-2 number, since 2×268187309² = 143848865417322962, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 268187309.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (268187209) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10314884 + ... + 10314909.

It is an arithmetic number, because the mean of its divisors is an integer number (72204279).

Almost surely, 2^268187309 is an apocalyptic number.

It is an amenable number.

268187309 is a deficient number, since it is larger than the sum of its proper divisors (20629807).

268187309 is a wasteful number, since it uses less digits than its factorization.

268187309 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20629806.

The product of its (nonzero) digits is 145152, while the sum is 44.

The square root of 268187309 is about 16376.4254036099. The cubic root of 268187309 is about 644.8807415267.

The spelling of 268187309 in words is "two hundred sixty-eight million, one hundred eighty-seven thousand, three hundred nine".