1263440 has 40 divisors (see below), whose sum is σ = 3113640. Its totient is φ = 475136.

The previous prime is 1263403. The next prime is 1263461. The reversal of 1263440 is 443621.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 26896 + 1236544 = 164^2 + 1112^2 .

It is a tau number, because it is divible by the number of its divisors (40).

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 896 + ... + 1824.

It is an arithmetic number, because the mean of its divisors is an integer number (77841).

2^1263440 is an apocalyptic number.

1263440 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 1263440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1556820).

1263440 is an abundant number, since it is smaller than the sum of its proper divisors (1850200).

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

1263440 is a wasteful number, since it uses less digits than its factorization.

1263440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 959 (or 953 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 20.

The square root of 1263440 is about 1124.0284693903. The cubic root of 1263440 is about 108.1064337128.

The spelling of 1263440 in words is "one million, two hundred sixty-three thousand, four hundred forty".