1388665 has 16 divisors (see below), whose sum is σ = 1763280. Its totient is φ = 1048320.

The previous prime is 1388659. The next prime is 1388669. The reversal of 1388665 is 5668831.

It can be written as a sum of positive squares in 8 ways, for example, as 281961 + 1106704 = 531^2 + 1052^2 .

It is not a de Polignac number, because 1388665 - 2⁵ = 1388633 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1388669) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 8767 + ... + 8923.

It is an arithmetic number, because the mean of its divisors is an integer number (110205).

2^1388665 is an apocalyptic number.

It is an amenable number.

1388665 is a deficient number, since it is larger than the sum of its proper divisors (374615).

1388665 is a wasteful number, since it uses less digits than its factorization.

1388665 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 252.

The product of its digits is 34560, while the sum is 37.

The square root of 1388665 is about 1178.4163101383. The cubic root of 1388665 is about 111.5661628809.

The spelling of 1388665 in words is "one million, three hundred eighty-eight thousand, six hundred sixty-five".