118138905 has 20 divisors (see below), whose sum is σ = 211775652. Its totient is φ = 63007200.

The previous prime is 118138897. The next prime is 118138907. The reversal of 118138905 is 509831811.

It can be written as a sum of positive squares in 2 ways, for example, as 80353296 + 37785609 = 8964^2 + 6147^2 .

It is not a de Polignac number, because 118138905 - 2³ = 118138897 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 118138905.

It is not an unprimeable number, because it can be changed into a prime (118138907) 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 in 19 ways as a sum of consecutive naturals, for example, 145446 + ... + 146255.

Almost surely, 2^118138905 is an apocalyptic number.

118138905 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

118138905 is a deficient number, since it is larger than the sum of its proper divisors (93636747).

118138905 is an equidigital number, since it uses as much as digits as its factorization.

118138905 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 291718 (or 291709 counting only the distinct ones).

The product of its (nonzero) digits is 8640, while the sum is 36.

The square root of 118138905 is about 10869.1722315915. The cubic root of 118138905 is about 490.6791983346.

The spelling of 118138905 in words is "one hundred eighteen million, one hundred thirty-eight thousand, nine hundred five".