268661989 has 4 divisors (see below), whose sum is σ = 269020480. Its totient is φ = 268303500.

The previous prime is 268661977. The next prime is 268661993. The reversal of 268661989 is 989166862.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 268661989 - 2¹⁷ = 268530917 is a prime.

It is a super-2 number, since 2×268661989² = 144358528666872242, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (268661909) 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, 178119 + ... + 179620.

It is an arithmetic number, because the mean of its divisors is an integer number (67255120).

Almost surely, 2^268661989 is an apocalyptic number.

It is an amenable number.

268661989 is a deficient number, since it is larger than the sum of its proper divisors (358491).

268661989 is an equidigital number, since it uses as much as digits as its factorization.

268661989 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 358490.

The product of its digits is 2239488, while the sum is 55.

The square root of 268661989 is about 16390.9117806179. The cubic root of 268661989 is about 645.2609876654.

The spelling of 268661989 in words is "two hundred sixty-eight million, six hundred sixty-one thousand, nine hundred eighty-nine".