1388944445 has 18 divisors (see below), whose sum is σ = 1939667706. Its totient is φ = 952019040.

The previous prime is 1388944433. The next prime is 1388944457. The reversal of 1388944445 is 5444498831.

It is an interprime number because it is at equal distance from previous prime (1388944433) and next prime (1388944457).

It can be written as a sum of positive squares in 3 ways, for example, as 246301636 + 1142642809 = 15694^2 + 33803^2 .

It is not a de Polignac number, because 1388944445 - 2³⁰ = 315202621 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 1388944393 and 1388944402.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 582155 + ... + 584535.

It is an arithmetic number, because the mean of its divisors is an integer number (107759317).

Almost surely, 2^1388944445 is an apocalyptic number.

It is an amenable number.

1388944445 is a deficient number, since it is larger than the sum of its proper divisors (550723261).

1388944445 is an frugal number, since it uses more digits than its factorization.

1388944445 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4781 (or 2393 counting only the distinct ones).

The product of its digits is 2211840, while the sum is 50.

The square root of 1388944445 is about 37268.5449809890. The cubic root of 1388944445 is about 1115.7364597085.

The spelling of 1388944445 in words is "one billion, three hundred eighty-eight million, nine hundred forty-four thousand, four hundred forty-five".