18030240538 has 4 divisors (see below), whose sum is σ = 27045360810. Its totient is φ = 9015120268.

The previous prime is 18030240521. The next prime is 18030240539. The reversal of 18030240538 is 83504203081.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 14129363689 + 3900876849 = 118867^2 + 62457^2 .

It is not an unprimeable number, because it can be changed into a prime (18030240539) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4507560133 + ... + 4507560136.

Almost surely, 2^18030240538 is an apocalyptic number.

18030240538 is a deficient number, since it is larger than the sum of its proper divisors (9015120272).

18030240538 is an equidigital number, since it uses as much as digits as its factorization.

18030240538 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9015120271.

The product of its (nonzero) digits is 23040, while the sum is 34.

The spelling of 18030240538 in words is "eighteen billion, thirty million, two hundred forty thousand, five hundred thirty-eight".