18530378274521 has 4 divisors (see below), whose sum is σ = 18924641642112. Its totient is φ = 18136114906932.

The previous prime is 18530378274517. The next prime is 18530378274523. The reversal of 18530378274521 is 12547287303581.

It is a happy number.

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 not a de Polignac number, because 18530378274521 - 2² = 18530378274517 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18530378274523) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 197131683725 + ... + 197131683818.

It is an arithmetic number, because the mean of its divisors is an integer number (4731160410528).

Almost surely, 2^{18530378274521} is an apocalyptic number.

It is an amenable number.

18530378274521 is a deficient number, since it is larger than the sum of its proper divisors (394263367591).

18530378274521 is an equidigital number, since it uses as much as digits as its factorization.

18530378274521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 394263367590.

The product of its (nonzero) digits is 11289600, while the sum is 56.

The spelling of 18530378274521 in words is "eighteen trillion, five hundred thirty billion, three hundred seventy-eight million, two hundred seventy-four thousand, five hundred twenty-one".