1161605 has 8 divisors (see below), whose sum is σ = 1423872. Its totient is φ = 909328.

The previous prime is 1161599. The next prime is 1161617. The reversal of 1161605 is 5061611.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1161605 - 2¹⁰ = 1160581 is a prime.

It is a Duffinian number.

It is a plaindrome in base 14.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2237 + ... + 2706.

It is an arithmetic number, because the mean of its divisors is an integer number (177984).

2^1161605 is an apocalyptic number.

It is an amenable number.

1161605 is a deficient number, since it is larger than the sum of its proper divisors (262267).

1161605 is an equidigital number, since it uses as much as digits as its factorization.

1161605 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4995.

The product of its (nonzero) digits is 180, while the sum is 20.

The square root of 1161605 is about 1077.7778064147. Note that the first 3 decimals coincide. The cubic root of 1161605 is about 105.1201949362.

It can be divided in two parts, 11 and 61605, that added together give a palindrome (61616).

The spelling of 1161605 in words is "one million, one hundred sixty-one thousand, six hundred five".