18131101 has 4 divisors (see below), whose sum is σ = 18349632. Its totient is φ = 17912572.

The previous prime is 18131081. The next prime is 18131117. The reversal of 18131101 is 10113181.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18131101 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 (18131161) 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 3 ways as a sum of consecutive naturals, for example, 109141 + ... + 109306.

It is an arithmetic number, because the mean of its divisors is an integer number (4587408).

Almost surely, 2^18131101 is an apocalyptic number.

It is an amenable number.

18131101 is a deficient number, since it is larger than the sum of its proper divisors (218531).

18131101 is an equidigital number, since it uses as much as digits as its factorization.

18131101 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 218530.

The product of its (nonzero) digits is 24, while the sum is 16.

The square root of 18131101 is about 4258.0630573067. The cubic root of 18131101 is about 262.7088635501.

Adding to 18131101 its reverse (10113181), we get a palindrome (28244282).

The spelling of 18131101 in words is "eighteen million, one hundred thirty-one thousand, one hundred one".