1387740 has 48 divisors (see below), whose sum is σ = 3941280. Its totient is φ = 364800.

The previous prime is 1387733. The next prime is 1387781. The reversal of 1387740 is 477831.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 1387698 and 1387707.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5946 + ... + 6174.

It is an arithmetic number, because the mean of its divisors is an integer number (82110).

2^1387740 is an apocalyptic number.

1387740 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 1387740, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1970640).

1387740 is an abundant number, since it is smaller than the sum of its proper divisors (2553540).

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

1387740 is a wasteful number, since it uses less digits than its factorization.

1387740 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 342 (or 340 counting only the distinct ones).

The product of its (nonzero) digits is 4704, while the sum is 30.

The square root of 1387740 is about 1178.0237688604. The cubic root of 1387740 is about 111.5413856973.

Subtracting from 1387740 its reverse (477831), we obtain a palindrome (909909).

The spelling of 1387740 in words is "one million, three hundred eighty-seven thousand, seven hundred forty".