1201311161 has 4 divisors (see below), whose sum is σ = 1210770432. Its totient is φ = 1191851892.

The previous prime is 1201311143. The next prime is 1201311169. The reversal of 1201311161 is 1611131021.

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 1201311161 - 2²⁶ = 1134202297 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1201311169) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4729445 + ... + 4729698.

It is an arithmetic number, because the mean of its divisors is an integer number (302692608).

Almost surely, 2^1201311161 is an apocalyptic number.

It is an amenable number.

1201311161 is a deficient number, since it is larger than the sum of its proper divisors (9459271).

1201311161 is an equidigital number, since it uses as much as digits as its factorization.

1201311161 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9459270.

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

The square root of 1201311161 is about 34659.9359635877. The cubic root of 1201311161 is about 1063.0454606599.

Adding to 1201311161 its reverse (1611131021), we get a palindrome (2812442182).

The spelling of 1201311161 in words is "one billion, two hundred one million, three hundred eleven thousand, one hundred sixty-one".