18280513 has 4 divisors (see below), whose sum is σ = 18401728. Its totient is φ = 18159300.

The previous prime is 18280487. The next prime is 18280517. The reversal of 18280513 is 31508281.

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 18280513 - 2¹³ = 18272321 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18280517) 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, 60381 + ... + 60682.

It is an arithmetic number, because the mean of its divisors is an integer number (4600432).

Almost surely, 2^18280513 is an apocalyptic number.

It is an amenable number.

18280513 is a deficient number, since it is larger than the sum of its proper divisors (121215).

18280513 is a wasteful number, since it uses less digits than its factorization.

18280513 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 121214.

The product of its (nonzero) digits is 1920, while the sum is 28.

The square root of 18280513 is about 4275.5716576851. The cubic root of 18280513 is about 263.4285206633.

Adding to 18280513 its reverse (31508281), we get a palindrome (49788794).

The spelling of 18280513 in words is "eighteen million, two hundred eighty thousand, five hundred thirteen".