1398909 has 4 divisors (see below), whose sum is σ = 1865216. Its totient is φ = 932604.

The previous prime is 1398871. The next prime is 1398911. The reversal of 1398909 is 9098931.

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.

It is not a de Polignac number, because 1398909 - 2⁷ = 1398781 is a prime.

It is a D-number.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1398979) 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, 233149 + ... + 233154.

It is an arithmetic number, because the mean of its divisors is an integer number (466304).

2^1398909 is an apocalyptic number.

It is an amenable number.

1398909 is a deficient number, since it is larger than the sum of its proper divisors (466307).

1398909 is an equidigital number, since it uses as much as digits as its factorization.

1398909 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 466306.

The product of its (nonzero) digits is 17496, while the sum is 39.

The square root of 1398909 is about 1182.7548351201. The cubic root of 1398909 is about 111.8398273793.

The spelling of 1398909 in words is "one million, three hundred ninety-eight thousand, nine hundred nine".