100138805 has 16 divisors (see below), whose sum is σ = 129702384. Its totient is φ = 73781760.

The previous prime is 100138781. The next prime is 100138807. The reversal of 100138805 is 508831001.

It can be written as a sum of positive squares in 8 ways, for example, as 27019204 + 73119601 = 5198^2 + 8551^2 .

It is a de Polignac number, because none of the positive numbers 2^k-100138805 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (100138807) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 32387 + ... + 35343.

It is an arithmetic number, because the mean of its divisors is an integer number (8106399).

Almost surely, 2^100138805 is an apocalyptic number.

It is an amenable number.

100138805 is a deficient number, since it is larger than the sum of its proper divisors (29563579).

100138805 is a wasteful number, since it uses less digits than its factorization.

100138805 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3496.

The product of its (nonzero) digits is 960, while the sum is 26.

The square root of 100138805 is about 10006.9378433165. The cubic root of 100138805 is about 464.3735426520.

Adding to 100138805 its reverse (508831001), we get a palindrome (608969806).

The spelling of 100138805 in words is "one hundred million, one hundred thirty-eight thousand, eight hundred five".