1156605 has 16 divisors (see below), whose sum is σ = 1874880. Its totient is φ = 608768.

The previous prime is 1156591. The next prime is 1156613. The reversal of 1156605 is 5066511.

It is a cyclic number.

It is not a de Polignac number, because 1156605 - 2⁶ = 1156541 is a prime.

It is a Curzon number.

1156605 is a lucky number.

It is a congruent number.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 781 + ... + 1709.

It is an arithmetic number, because the mean of its divisors is an integer number (117180).

2^1156605 is an apocalyptic number.

1156605 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1156605 is a deficient number, since it is larger than the sum of its proper divisors (718275).

1156605 is an equidigital number, since it uses as much as digits as its factorization.

1156605 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1020.

The product of its (nonzero) digits is 900, while the sum is 24.

The square root of 1156605 is about 1075.4557173589. The cubic root of 1156605 is about 104.9691519357.

It can be divided in two parts, 11 and 56605, that added together give a triangular number (56616 = T₃₃₆).

The spelling of 1156605 in words is "one million, one hundred fifty-six thousand, six hundred five".