1399509 has 6 divisors (see below), whose sum is σ = 2021526. Its totient is φ = 933000.

The previous prime is 1399507. The next prime is 1399513. The reversal of 1399509 is 9059931.

It can be written as a sum of positive squares in only one way, i.e., 1258884 + 140625 = 1122^2 + 375^2 .

It is not a de Polignac number, because 1399509 - 2¹ = 1399507 is a prime.

It is a nialpdrome in base 11.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1399507) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 77742 + ... + 77759.

It is an arithmetic number, because the mean of its divisors is an integer number (336921).

2^1399509 is an apocalyptic number.

It is an amenable number.

1399509 is a deficient number, since it is larger than the sum of its proper divisors (622017).

1399509 is a wasteful number, since it uses less digits than its factorization.

1399509 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 155507 (or 155504 counting only the distinct ones).

The product of its (nonzero) digits is 10935, while the sum is 36.

The square root of 1399509 is about 1183.0084530552. The cubic root of 1399509 is about 111.8558146725.

The spelling of 1399509 in words is "one million, three hundred ninety-nine thousand, five hundred nine".