268639 has 4 divisors (see below), whose sum is σ = 307024. Its totient is φ = 230256.

The previous prime is 268637. The next prime is 268643. The reversal of 268639 is 936862.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 268639 - 2¹ = 268637 is a prime.

It is a Duffinian number.

268639 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (268637) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 19182 + ... + 19195.

It is an arithmetic number, because the mean of its divisors is an integer number (76756).

2²⁶⁸⁶³⁹ is an apocalyptic number.

268639 is a deficient number, since it is larger than the sum of its proper divisors (38385).

268639 is an equidigital number, since it uses as much as digits as its factorization.

268639 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 38384.

The product of its digits is 15552, while the sum is 34.

The square root of 268639 is about 518.3039648700. The cubic root of 268639 is about 64.5242582472.

The spelling of 268639 in words is "two hundred sixty-eight thousand, six hundred thirty-nine".