1388628 has 36 divisors (see below), whose sum is σ = 3718260. Its totient is φ = 435456.

The previous prime is 1388627. The next prime is 1388633. The reversal of 1388628 is 8268831.

It can be written as a sum of positive squares in 2 ways, for example, as 501264 + 887364 = 708^2 + 942^2 .

It is a tau number, because it is divible by the number of its divisors (36).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 1388592 and 1388601.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1388623) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 523 + ... + 1746.

It is an arithmetic number, because the mean of its divisors is an integer number (103285).

2^1388628 is an apocalyptic number.

1388628 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is an amenable number.

1388628 is an abundant number, since it is smaller than the sum of its proper divisors (2329632).

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

1388628 is a wasteful number, since it uses less digits than its factorization.

1388628 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2296 (or 2291 counting only the distinct ones).

The product of its digits is 18432, while the sum is 36.

The square root of 1388628 is about 1178.4006109978. The cubic root of 1388628 is about 111.5651720048.

It can be divided in two parts, 1388 and 628, that added together give a triangular number (2016 = T₆₃).

The spelling of 1388628 in words is "one million, three hundred eighty-eight thousand, six hundred twenty-eight".