1906865 has 4 divisors (see below), whose sum is σ = 2288244. Its totient is φ = 1525488.

The previous prime is 1906843. The next prime is 1906867. The reversal of 1906865 is 5686091.

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 1073296 + 833569 = 1036^2 + 913^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1906865 is a prime.

It is a super-2 number, since 2×1906865² = 7272268256450, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1906867) 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, 190682 + ... + 190691.

It is an arithmetic number, because the mean of its divisors is an integer number (572061).

2^1906865 is an apocalyptic number.

It is an amenable number.

1906865 is a deficient number, since it is larger than the sum of its proper divisors (381379).

1906865 is an equidigital number, since it uses as much as digits as its factorization.

1906865 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 381378.

The product of its (nonzero) digits is 12960, while the sum is 35.

The square root of 1906865 is about 1380.8928271231. The cubic root of 1906865 is about 124.0052243723.

The spelling of 1906865 in words is "one million, nine hundred six thousand, eight hundred sixty-five".