18280913 has 4 divisors (see below), whose sum is σ = 20892480. Its totient is φ = 15669348.

The previous prime is 18280909. The next prime is 18280921. The reversal of 18280913 is 31908281.

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: 31908281 = 67 ⋅476243.

It is a cyclic number.

It is not a de Polignac number, because 18280913 - 2² = 18280909 is a prime.

It is a super-2 number, since 2×18280913² = 668383560227138, which contains 22 as substring.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 18280913.

It is not an unprimeable number, because it can be changed into a prime (18280903) 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, 1305773 + ... + 1305786.

It is an arithmetic number, because the mean of its divisors is an integer number (5223120).

Almost surely, 2^18280913 is an apocalyptic number.

It is an amenable number.

18280913 is a deficient number, since it is larger than the sum of its proper divisors (2611567).

18280913 is an equidigital number, since it uses as much as digits as its factorization.

18280913 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2611566.

The product of its (nonzero) digits is 3456, while the sum is 32.

The square root of 18280913 is about 4275.6184347998. The cubic root of 18280913 is about 263.4304420287.

The spelling of 18280913 in words is "eighteen million, two hundred eighty thousand, nine hundred thirteen".