1161203111 has 4 divisors (see below), whose sum is σ = 1161721224. Its totient is φ = 1160685000.

The previous prime is 1161203101. The next prime is 1161203143. The reversal of 1161203111 is 1113021611.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1161203111 - 2³⁰ = 87461287 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1161203111.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1161203101) 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, 255680 + ... + 260181.

It is an arithmetic number, because the mean of its divisors is an integer number (290430306).

Almost surely, 2^1161203111 is an apocalyptic number.

1161203111 is a deficient number, since it is larger than the sum of its proper divisors (518113).

1161203111 is an equidigital number, since it uses as much as digits as its factorization.

1161203111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 518112.

The product of its (nonzero) digits is 36, while the sum is 17.

The square root of 1161203111 is about 34076.4304321917. The cubic root of 1161203111 is about 1051.0807046958.

Adding to 1161203111 its reverse (1113021611), we get a palindrome (2274224722).

The spelling of 1161203111 in words is "one billion, one hundred sixty-one million, two hundred three thousand, one hundred eleven".