1388655 has 12 divisors (see below), whose sum is σ = 2407080. Its totient is φ = 740592.

The previous prime is 1388641. The next prime is 1388659. The reversal of 1388655 is 5568831.

1388655 = 525² + 526² + ... + 529².

It is not a de Polignac number, because 1388655 - 2⁵ = 1388623 is a prime.

It is a super-3 number, since 3×1388655³ = 8033491553103334125, which contains 333 as substring.

It is a Smith number, since the sum of its digits (36) coincides with the sum of the digits of its prime factors.

1388655 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1388659) 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 11 ways as a sum of consecutive naturals, for example, 15385 + ... + 15474.

It is an arithmetic number, because the mean of its divisors is an integer number (200590).

2^1388655 is an apocalyptic number.

1388655 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

1388655 is a deficient number, since it is larger than the sum of its proper divisors (1018425).

1388655 is a wasteful number, since it uses less digits than its factorization.

1388655 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30870 (or 30867 counting only the distinct ones).

The product of its digits is 28800, while the sum is 36.

The square root of 1388655 is about 1178.4120671480. The cubic root of 1388655 is about 111.5658950783.

The spelling of 1388655 in words is "one million, three hundred eighty-eight thousand, six hundred fifty-five".