1390040 has 64 divisors (see below), whose sum is σ = 3456000. Its totient is φ = 501120.

The previous prime is 1390027. The next prime is 1390043. The reversal of 1390040 is 400931.

It is a Cunningham number, because it is equal to 1179²-1.

It is a super-2 number, since 2×1390040² = 3864422403200, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1390043) by changing a digit.

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, 23531 + ... + 23589.

It is an arithmetic number, because the mean of its divisors is an integer number (54000).

2^1390040 is an apocalyptic number.

1390040 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 1390040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1728000).

1390040 is an abundant number, since it is smaller than the sum of its proper divisors (2065960).

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

1390040 is a wasteful number, since it uses less digits than its factorization.

1390040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 120 (or 116 counting only the distinct ones).

The product of its (nonzero) digits is 108, while the sum is 17.

The square root of 1390040 is about 1178.9995759117. Note that the first 3 decimals coincide. The cubic root of 1390040 is about 111.6029735037.

Adding to 1390040 its reverse (400931), we get a palindrome (1790971).

The spelling of 1390040 in words is "one million, three hundred ninety thousand, forty".