1158661 has 4 divisors (see below), whose sum is σ = 1324192. Its totient is φ = 993132.

The previous prime is 1158653. The next prime is 1158673. The reversal of 1158661 is 1668511.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 1668511 = 13 ⋅128347.

It is not a de Polignac number, because 1158661 - 2³ = 1158653 is a prime.

It is a Duffinian number.

It is a plaindrome in base 14.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1158611) 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, 82755 + ... + 82768.

It is an arithmetic number, because the mean of its divisors is an integer number (331048).

2^1158661 is an apocalyptic number.

It is an amenable number.

1158661 is a deficient number, since it is larger than the sum of its proper divisors (165531).

1158661 is an equidigital number, since it uses as much as digits as its factorization.

1158661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 165530.

The product of its digits is 1440, while the sum is 28.

The square root of 1158661 is about 1076.4111667945. The cubic root of 1158661 is about 105.0313134120.

The spelling of 1158661 in words is "one million, one hundred fifty-eight thousand, six hundred sixty-one".