268689640 has 128 divisors (see below), whose sum is σ = 671328000. Its totient is φ = 96380928.

The previous prime is 268689623. The next prime is 268689661. The reversal of 268689640 is 46986862.

268689640 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1608837 + ... + 1609003.

It is an arithmetic number, because the mean of its divisors is an integer number (5244750).

Almost surely, 2^268689640 is an apocalyptic number.

268689640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 268689640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (335664000).

268689640 is an abundant number, since it is smaller than the sum of its proper divisors (402638360).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

268689640 is a wasteful number, since it uses less digits than its factorization.

268689640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 299 (or 295 counting only the distinct ones).

The product of its (nonzero) digits is 995328, while the sum is 49.

The square root of 268689640 is about 16391.7552446344. The cubic root of 268689640 is about 645.2831239063.

The spelling of 268689640 in words is "two hundred sixty-eight million, six hundred eighty-nine thousand, six hundred forty".