1381440 has 56 divisors (see below), whose sum is σ = 4389120. Its totient is φ = 368128.

The previous prime is 1381439. The next prime is 1381441. The reversal of 1381440 is 441831.

It is an interprime number because it is at equal distance from previous prime (1381439) and next prime (1381441).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1381441) 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, 241 + ... + 1679.

2^1381440 is an apocalyptic number.

1381440 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 1381440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2194560).

1381440 is an abundant number, since it is smaller than the sum of its proper divisors (3007680).

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

1381440 is a wasteful number, since it uses less digits than its factorization.

1381440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1459 (or 1449 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 21.

The square root of 1381440 is about 1175.3467573444. The cubic root of 1381440 is about 111.3723394307.

The spelling of 1381440 in words is "one million, three hundred eighty-one thousand, four hundred forty".