1156986161 has 4 divisors (see below), whose sum is σ = 1157414400. Its totient is φ = 1156557924.

The previous prime is 1156986157. The next prime is 1156986163. The reversal of 1156986161 is 1616896511.

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 1156986161 - 2² = 1156986157 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1156986163) 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, 210041 + ... + 215478.

It is an arithmetic number, because the mean of its divisors is an integer number (289353600).

Almost surely, 2^1156986161 is an apocalyptic number.

It is an amenable number.

1156986161 is a deficient number, since it is larger than the sum of its proper divisors (428239).

1156986161 is an equidigital number, since it uses as much as digits as its factorization.

1156986161 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 428238.

The product of its digits is 77760, while the sum is 44.

The square root of 1156986161 is about 34014.4992760440. The cubic root of 1156986161 is about 1049.8068158576.

The spelling of 1156986161 in words is "one billion, one hundred fifty-six million, nine hundred eighty-six thousand, one hundred sixty-one".