1264640 has 88 divisors (see below), whose sum is σ = 3438960. Its totient is φ = 442368.

The previous prime is 1264607. The next prime is 1264643. The reversal of 1264640 is 464621.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (1264643) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 66551 + ... + 66569.

2^1264640 is an apocalyptic number.

1264640 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 1264640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1719480).

1264640 is an abundant number, since it is smaller than the sum of its proper divisors (2174320).

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

1264640 is a wasteful number, since it uses less digits than its factorization.

1264640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 57 (or 39 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 23.

The square root of 1264640 is about 1124.5621370116. The cubic root of 1264640 is about 108.1406489429.

The spelling of 1264640 in words is "one million, two hundred sixty-four thousand, six hundred forty".