18732013 has 4 divisors (see below), whose sum is σ = 18775708. Its totient is φ = 18688320.

The previous prime is 18731989. The next prime is 18732017. The reversal of 18732013 is 31023781.

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

It can be written as a sum of positive squares in 2 ways, for example, as 5750404 + 12981609 = 2398^2 + 3603^2 .

It is a cyclic number.

It is not a de Polignac number, because 18732013 - 2⁵ = 18731981 is a prime.

It is a super-2 number, since 2×18732013² = 701776622064338, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18732017) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 21198 + ... + 22063.

It is an arithmetic number, because the mean of its divisors is an integer number (4693927).

Almost surely, 2^18732013 is an apocalyptic number.

It is an amenable number.

18732013 is a deficient number, since it is larger than the sum of its proper divisors (43695).

18732013 is an equidigital number, since it uses as much as digits as its factorization.

18732013 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43694.

The product of its (nonzero) digits is 1008, while the sum is 25.

The square root of 18732013 is about 4328.0495607144. The cubic root of 18732013 is about 265.5796638289.

Adding to 18732013 its reverse (31023781), we get a palindrome (49755794).

The spelling of 18732013 in words is "eighteen million, seven hundred thirty-two thousand, thirteen".