1390909 has 4 divisors (see below), whose sum is σ = 1497916. Its totient is φ = 1283904.

The previous prime is 1390903. The next prime is 1390913. The reversal of 1390909 is 9090931.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 931225 + 459684 = 965^2 + 678^2 .

It is a cyclic number.

It is not a de Polignac number, because 1390909 - 2³ = 1390901 is a prime.

It is an Ulam number.

It is a Duffinian number.

1390909 is a modest number, since divided by 909 gives 139 as remainder.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1390901) 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, 53484 + ... + 53509.

It is an arithmetic number, because the mean of its divisors is an integer number (374479).

2^1390909 is an apocalyptic number.

It is an amenable number.

1390909 is a deficient number, since it is larger than the sum of its proper divisors (107007).

1390909 is a wasteful number, since it uses less digits than its factorization.

1390909 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 107006.

The product of its (nonzero) digits is 2187, while the sum is 31.

The square root of 1390909 is about 1179.3680511189. The cubic root of 1390909 is about 111.6262253000.

The spelling of 1390909 in words is "one million, three hundred ninety thousand, nine hundred nine".