1161905 has 4 divisors (see below), whose sum is σ = 1394292. Its totient is φ = 929520.

The previous prime is 1161893. The next prime is 1161929. The reversal of 1161905 is 5091611.

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 185761 + 976144 = 431^2 + 988^2 .

It is not a de Polignac number, because 1161905 - 2⁶ = 1161841 is a prime.

It is a Duffinian number.

It is an unprimeable number.

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, 116186 + ... + 116195.

It is an arithmetic number, because the mean of its divisors is an integer number (348573).

2^1161905 is an apocalyptic number.

It is an amenable number.

1161905 is a deficient number, since it is larger than the sum of its proper divisors (232387).

1161905 is an equidigital number, since it uses as much as digits as its factorization.

1161905 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 232386.

The product of its (nonzero) digits is 270, while the sum is 23.

The square root of 1161905 is about 1077.9169726839. The cubic root of 1161905 is about 105.1292437218.

It can be divided in two parts, 11 and 61905, that added together give a palindrome (61916).

The spelling of 1161905 in words is "one million, one hundred sixty-one thousand, nine hundred five".