1388945 has 4 divisors (see below), whose sum is σ = 1666740. Its totient is φ = 1111152.

The previous prime is 1388941. The next prime is 1388953. The reversal of 1388945 is 5498831.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 5498831 = 13 ⋅422987.

It can be written as a sum of positive squares in 2 ways, for example, as 786769 + 602176 = 887^2 + 776^2 .

It is a cyclic number.

It is not a de Polignac number, because 1388945 - 2² = 1388941 is a prime.

It is an Ulam number.

It is a junction number, because it is equal to n+sod(n) for n = 1388899 and 1388908.

It is not an unprimeable number, because it can be changed into a prime (1388941) 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, 138890 + ... + 138899.

It is an arithmetic number, because the mean of its divisors is an integer number (416685).

2^1388945 is an apocalyptic number.

It is an amenable number.

1388945 is a deficient number, since it is larger than the sum of its proper divisors (277795).

1388945 is an equidigital number, since it uses as much as digits as its factorization.

1388945 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 277794.

The product of its digits is 34560, while the sum is 38.

The square root of 1388945 is about 1178.5351076654. The cubic root of 1388945 is about 111.5736608319.

The spelling of 1388945 in words is "one million, three hundred eighty-eight thousand, nine hundred forty-five".