18231538090 has 8 divisors (see below), whose sum is σ = 32816768580. Its totient is φ = 7292615232.

The previous prime is 18231538067. The next prime is 18231538093. The reversal of 18231538090 is 9083513281.

It can be written as a sum of positive squares in 2 ways, for example, as 18198279801 + 33258289 = 134901^2 + 5767^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a super-2 number, since 2×18231538090² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (18231538093) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 911576895 + ... + 911576914.

Almost surely, 2^18231538090 is an apocalyptic number.

18231538090 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

18231538090 is a deficient number, since it is larger than the sum of its proper divisors (14585230490).

18231538090 is a wasteful number, since it uses less digits than its factorization.

18231538090 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1823153816.

The product of its (nonzero) digits is 51840, while the sum is 40.

The spelling of 18231538090 in words is "eighteen billion, two hundred thirty-one million, five hundred thirty-eight thousand, ninety".