18303681 has 16 divisors (see below), whose sum is σ = 27244800. Its totient is φ = 10834320.

The previous prime is 18303661. The next prime is 18303683. The reversal of 18303681 is 18630381.

It is not a de Polignac number, because 18303681 - 2²¹ = 16206529 is a prime.

It is a super-2 number, since 2×18303681² = 670049476299522, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (18303683) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5031 + ... + 7868.

It is an arithmetic number, because the mean of its divisors is an integer number (1702800).

Almost surely, 2^18303681 is an apocalyptic number.

18303681 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

18303681 is a deficient number, since it is larger than the sum of its proper divisors (8941119).

18303681 is a wasteful number, since it uses less digits than its factorization.

18303681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12956.

The product of its (nonzero) digits is 3456, while the sum is 30.

The square root of 18303681 is about 4278.2801451050. The cubic root of 18303681 is about 263.5397599832.

The spelling of 18303681 in words is "eighteen million, three hundred three thousand, six hundred eighty-one".