1268640 has 72 divisors (see below), whose sum is σ = 4334148. Its totient is φ = 337920.

The previous prime is 1268633. The next prime is 1268669. The reversal of 1268640 is 468621.

1268640 is a `hidden beast` number, since 12 + 6 + 8 + 640 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 1192464 + 76176 = 1092^2 + 276^2 .

It is a tau number, because it is divible by the number of its divisors (72).

It is a hoax number, since the sum of its digits (27) coincides with the sum of the digits of its distinct prime factors.

It is a plaindrome in base 13.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1000 + ... + 1880.

2^1268640 is an apocalyptic number.

1268640 is a gapful number since it is divisible by the number (10) 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 1268640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2167074).

1268640 is an abundant number, since it is smaller than the sum of its proper divisors (3065508).

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

1268640 is a wasteful number, since it uses less digits than its factorization.

1268640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 902 (or 891 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 27.

The square root of 1268640 is about 1126.3392029047. The cubic root of 1268640 is about 108.2545436314.

The spelling of 1268640 in words is "one million, two hundred sixty-eight thousand, six hundred forty".