1920009 has 24 divisors (see below), whose sum is σ = 3173952. Its totient is φ = 1010880.

The previous prime is 1920001. The next prime is 1920011. The reversal of 1920009 is 9000291.

It is a happy number.

It is not a de Polignac number, because 1920009 - 2³ = 1920001 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (21).

1920009 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (1920001) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 3279 + ... + 3819.

It is an arithmetic number, because the mean of its divisors is an integer number (132248).

2^1920009 is an apocalyptic number.

It is an amenable number.

1920009 is a deficient number, since it is larger than the sum of its proper divisors (1253943).

1920009 is a wasteful number, since it uses less digits than its factorization.

1920009 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 577 (or 564 counting only the distinct ones).

The product of its (nonzero) digits is 162, while the sum is 21.

The square root of 1920009 is about 1385.6438936466. The cubic root of 1920009 is about 124.2894944399.

It can be divided in two parts, 192000 and 9, that multiplied together give a cube (1728000 = 120³).

The spelling of 1920009 in words is "one million, nine hundred twenty thousand, nine".