1928009 has 4 divisors (see below), whose sum is σ = 1938960. Its totient is φ = 1917060.

The previous prime is 1927997. The next prime is 1928011. The reversal of 1928009 is 9008291.

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 a cyclic number.

It is not a de Polignac number, because 1928009 - 2⁴ = 1927993 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1928029) 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, 5207 + ... + 5564.

It is an arithmetic number, because the mean of its divisors is an integer number (484740).

2^1928009 is an apocalyptic number.

It is an amenable number.

1928009 is a deficient number, since it is larger than the sum of its proper divisors (10951).

1928009 is a wasteful number, since it uses less digits than its factorization.

1928009 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10950.

The product of its (nonzero) digits is 1296, while the sum is 29.

The square root of 1928009 is about 1388.5276374635. The cubic root of 1928009 is about 124.4618787283.

The spelling of 1928009 in words is "one million, nine hundred twenty-eight thousand, nine".