118145981 has 2 divisors, whose sum is σ = 118145982. Its totient is φ = 118145980.

The previous prime is 118145977. The next prime is 118146013. The reversal of 118145981 is 189541811.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 87796900 + 30349081 = 9370^2 + 5509^2 .

It is a cyclic number.

It is not a de Polignac number, because 118145981 - 2² = 118145977 is a prime.

It is a super-3 number, since 3×118145981³ (a number of 25 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (118145281) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 59072990 + 59072991.

It is an arithmetic number, because the mean of its divisors is an integer number (59072991).

Almost surely, 2^118145981 is an apocalyptic number.

It is an amenable number.

118145981 is a deficient number, since it is larger than the sum of its proper divisors (1).

118145981 is an equidigital number, since it uses as much as digits as its factorization.

118145981 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 11520, while the sum is 38.

The square root of 118145981 is about 10869.4977344862. The cubic root of 118145981 is about 490.6889946465.

The spelling of 118145981 in words is "one hundred eighteen million, one hundred forty-five thousand, nine hundred eighty-one".