1166861143 has 4 divisors (see below), whose sum is σ = 1333555600. Its totient is φ = 1000166688.

The previous prime is 1166861089. The next prime is 1166861149. The reversal of 1166861143 is 3411686611.

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 1166861143 - 2²¹ = 1164763991 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1166861149) 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, 83347218 + ... + 83347231.

It is an arithmetic number, because the mean of its divisors is an integer number (333388900).

Almost surely, 2^1166861143 is an apocalyptic number.

1166861143 is a deficient number, since it is larger than the sum of its proper divisors (166694457).

1166861143 is an equidigital number, since it uses as much as digits as its factorization.

1166861143 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 166694456.

The product of its digits is 20736, while the sum is 37.

The square root of 1166861143 is about 34159.3492765890. The cubic root of 1166861143 is about 1052.7850907621.

The spelling of 1166861143 in words is "one billion, one hundred sixty-six million, eight hundred sixty-one thousand, one hundred forty-three".