118243561 has 2 divisors, whose sum is σ = 118243562. Its totient is φ = 118243560.

The previous prime is 118243553. The next prime is 118243571. The reversal of 118243561 is 165342811.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 109599961 + 8643600 = 10469^2 + 2940^2 .

It is an emirp because it is prime and its reverse (165342811) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 118243561 - 2³ = 118243553 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (118243511) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 59121780 + 59121781.

It is an arithmetic number, because the mean of its divisors is an integer number (59121781).

Almost surely, 2^118243561 is an apocalyptic number.

It is an amenable number.

118243561 is a deficient number, since it is larger than the sum of its proper divisors (1).

118243561 is an equidigital number, since it uses as much as digits as its factorization.

118243561 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 5760, while the sum is 31.

The square root of 118243561 is about 10873.9855158999. The cubic root of 118243561 is about 490.8240486296.

The spelling of 118243561 in words is "one hundred eighteen million, two hundred forty-three thousand, five hundred sixty-one".