1890745 has 4 divisors (see below), whose sum is σ = 2268900. Its totient is φ = 1512592.

The previous prime is 1890743. The next prime is 1890769. The reversal of 1890745 is 5470981.

It is a happy number.

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 868624 + 1022121 = 932^2 + 1011^2 .

It is a cyclic number.

It is not a de Polignac number, because 1890745 - 2¹ = 1890743 is a prime.

It is an Ulam number.

It is an alternating number because its digits alternate between odd and even.

It is a nialpdrome in base 12.

It is a self number, because there is not a number n which added to its sum of digits gives 1890745.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1890743) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 189070 + ... + 189079.

It is an arithmetic number, because the mean of its divisors is an integer number (567225).

2^1890745 is an apocalyptic number.

It is an amenable number.

1890745 is a deficient number, since it is larger than the sum of its proper divisors (378155).

1890745 is an equidigital number, since it uses as much as digits as its factorization.

1890745 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 378154.

The product of its (nonzero) digits is 10080, while the sum is 34.

The square root of 1890745 is about 1375.0436356712. The cubic root of 1890745 is about 123.6548021382.

The spelling of 1890745 in words is "one million, eight hundred ninety thousand, seven hundred forty-five".