1904545 has 4 divisors (see below), whose sum is σ = 2285460. Its totient is φ = 1523632.

The previous prime is 1904543. The next prime is 1904549. The reversal of 1904545 is 5454091.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 5454091 = 461 ⋅11831.

It can be written as a sum of positive squares in 2 ways, for example, as 1183744 + 720801 = 1088^2 + 849^2 .

It is a cyclic number.

It is not a de Polignac number, because 1904545 - 2¹ = 1904543 is a prime.

It is an Ulam number.

1904545 is a modest number, since divided by 4545 gives 190 as remainder.

It is not an unprimeable number, because it can be changed into a prime (1904543) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 190450 + ... + 190459.

It is an arithmetic number, because the mean of its divisors is an integer number (571365).

2^1904545 is an apocalyptic number.

It is an amenable number.

1904545 is a deficient number, since it is larger than the sum of its proper divisors (380915).

1904545 is an equidigital number, since it uses as much as digits as its factorization.

1904545 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 380914.

The product of its (nonzero) digits is 3600, while the sum is 28.

The square root of 1904545 is about 1380.0525352319. The cubic root of 1904545 is about 123.9549133691.

The spelling of 1904545 in words is "one million, nine hundred four thousand, five hundred forty-five".