1181561142 has 16 divisors (see below), whose sum is σ = 2367864000. Its totient is φ = 393063432.

The previous prime is 1181561141. The next prime is 1181561167. The reversal of 1181561142 is 2411651811.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1181561141) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 194328 + ... + 200315.

It is an arithmetic number, because the mean of its divisors is an integer number (147991500).

Almost surely, 2^1181561142 is an apocalyptic number.

1181561142 is an abundant number, since it is smaller than the sum of its proper divisors (1186302858).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1181561142 is a wasteful number, since it uses less digits than its factorization.

1181561142 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 395147.

The product of its digits is 1920, while the sum is 30.

The square root of 1181561142 is about 34373.8438641942. The cubic root of 1181561142 is about 1057.1876148099.

The spelling of 1181561142 in words is "one billion, one hundred eighty-one million, five hundred sixty-one thousand, one hundred forty-two".