18988513 has 4 divisors (see below), whose sum is σ = 19015360. Its totient is φ = 18961668.

The previous prime is 18988483. The next prime is 18988573. The reversal of 18988513 is 31588981.

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, and also an emirpimes, since its reverse is a distinct semiprime: 31588981 = 2441 ⋅12941.

It is a cyclic number.

It is not a de Polignac number, because 18988513 - 2¹³ = 18980321 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 18988513.

It is not an unprimeable number, because it can be changed into a prime (18988573) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 12333 + ... + 13786.

It is an arithmetic number, because the mean of its divisors is an integer number (4753840).

Almost surely, 2^18988513 is an apocalyptic number.

It is an amenable number.

18988513 is a deficient number, since it is larger than the sum of its proper divisors (26847).

18988513 is an equidigital number, since it uses as much as digits as its factorization.

18988513 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26846.

The product of its digits is 69120, while the sum is 43.

The square root of 18988513 is about 4357.5810950572. The cubic root of 18988513 is about 266.7863787161.

The spelling of 18988513 in words is "eighteen million, nine hundred eighty-eight thousand, five hundred thirteen".