118418642581 has 2 divisors, whose sum is σ = 118418642582. Its totient is φ = 118418642580.

The previous prime is 118418642549. The next prime is 118418642593. The reversal of 118418642581 is 185246814811.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 103968198481 + 14450444100 = 322441^2 + 120210^2 .

It is a cyclic number.

It is not a de Polignac number, because 118418642581 - 2⁵ = 118418642549 is a prime.

It is a super-2 number, since 2×118418642581² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (118418645581) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 59209321290 + 59209321291.

It is an arithmetic number, because the mean of its divisors is an integer number (59209321291).

Almost surely, 2^118418642581 is an apocalyptic number.

It is an amenable number.

118418642581 is a deficient number, since it is larger than the sum of its proper divisors (1).

118418642581 is an equidigital number, since it uses as much as digits as its factorization.

118418642581 is an evil number, because the sum of its binary digits is even.

The product of its digits is 491520, while the sum is 49.

The spelling of 118418642581 in words is "one hundred eighteen billion, four hundred eighteen million, six hundred forty-two thousand, five hundred eighty-one".