1388778 has 8 divisors (see below), whose sum is σ = 2777568. Its totient is φ = 462924.

The previous prime is 1388773. The next prime is 1388789. The reversal of 1388778 is 8778831.

It is a sphenic number, since it is the product of 3 distinct primes.

1388778 is an admirable number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (1388773) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 115726 + ... + 115737.

It is an arithmetic number, because the mean of its divisors is an integer number (347196).

2^1388778 is an apocalyptic number.

1388778 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

1388778 is a wasteful number, since it uses less digits than its factorization.

1388778 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 231468.

The product of its digits is 75264, while the sum is 42.

The square root of 1388778 is about 1178.4642548673. The cubic root of 1388778 is about 111.5691889610.

The spelling of 1388778 in words is "one million, three hundred eighty-eight thousand, seven hundred seventy-eight".