1231161 has 4 divisors (see below), whose sum is σ = 1641552. Its totient is φ = 820772.

The previous prime is 1231141. The next prime is 1231171. The reversal of 1231161 is 1611321.

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.

It is a cyclic number.

It is not a de Polignac number, because 1231161 - 2⁵ = 1231129 is a prime.

It is a D-number.

It is a self number, because there is not a number n which added to its sum of digits gives 1231161.

It is not an unprimeable number, because it can be changed into a prime (1231141) 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, 205191 + ... + 205196.

It is an arithmetic number, because the mean of its divisors is an integer number (410388).

2^1231161 is an apocalyptic number.

It is an amenable number.

1231161 is a deficient number, since it is larger than the sum of its proper divisors (410391).

1231161 is an equidigital number, since it uses as much as digits as its factorization.

1231161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 410390.

The product of its digits is 36, while the sum is 15.

The square root of 1231161 is about 1109.5769464080. The cubic root of 1231161 is about 107.1778275689.

Adding to 1231161 its reverse (1611321), we get a palindrome (2842482).

The spelling of 1231161 in words is "one million, two hundred thirty-one thousand, one hundred sixty-one".