1375989 has 4 divisors (see below), whose sum is σ = 1834656. Its totient is φ = 917324.

The previous prime is 1375987. The next prime is 1376003. The reversal of 1375989 is 9895731.

1375989 = 387² + 388² + ... + 395².

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 9895731 = 3 ⋅3298577.

It is a cyclic number.

It is not a de Polignac number, because 1375989 - 2¹ = 1375987 is a prime.

It is a D-number.

1375989 is a lucky number.

It is a self number, because there is not a number n which added to its sum of digits gives 1375989.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1375981) 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, 229329 + ... + 229334.

It is an arithmetic number, because the mean of its divisors is an integer number (458664).

2^1375989 is an apocalyptic number.

It is an amenable number.

1375989 is a deficient number, since it is larger than the sum of its proper divisors (458667).

1375989 is an equidigital number, since it uses as much as digits as its factorization.

1375989 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 458666.

The product of its digits is 68040, while the sum is 42.

The square root of 1375989 is about 1173.0255751688. The cubic root of 1375989 is about 111.2256589426.

The spelling of 1375989 in words is "one million, three hundred seventy-five thousand, nine hundred eighty-nine".