1090805 has 16 divisors (see below), whose sum is σ = 1424304. Its totient is φ = 798720.

The previous prime is 1090799. The next prime is 1090807. The reversal of 1090805 is 5080901.

It can be written as a sum of positive squares in 8 ways, for example, as 305809 + 784996 = 553^2 + 886^2 .

It is a de Polignac number, because none of the positive numbers 2^k-1090805 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1090807) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3329 + ... + 3641.

It is an arithmetic number, because the mean of its divisors is an integer number (89019).

2^1090805 is an apocalyptic number.

It is an amenable number.

1090805 is a deficient number, since it is larger than the sum of its proper divisors (333499).

1090805 is a wasteful number, since it uses less digits than its factorization.

1090805 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 376.

The product of its (nonzero) digits is 360, while the sum is 23.

The square root of 1090805 is about 1044.4161048165. The cubic root of 1090805 is about 102.9395755813.

The spelling of 1090805 in words is "one million, ninety thousand, eight hundred five".