1181687978 has 16 divisors (see below), whose sum is σ = 1842873984. Its totient is φ = 567827040.

The previous prime is 1181687971. The next prime is 1181687999. The reversal of 1181687978 is 8797861811.

It is not an unprimeable number, because it can be changed into a prime (1181687971) 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, 102050 + ... + 113037.

It is an arithmetic number, because the mean of its divisors is an integer number (115179624).

Almost surely, 2^1181687978 is an apocalyptic number.

1181687978 is a deficient number, since it is larger than the sum of its proper divisors (661186006).

1181687978 is a wasteful number, since it uses less digits than its factorization.

1181687978 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 215197.

The product of its digits is 1354752, while the sum is 56.

The square root of 1181687978 is about 34375.6887640088. The cubic root of 1181687978 is about 1057.2254417847.

The spelling of 1181687978 in words is "one billion, one hundred eighty-one million, six hundred eighty-seven thousand, nine hundred seventy-eight".