18290731 has 4 divisors (see below), whose sum is σ = 18321472. Its totient is φ = 18259992.

The previous prime is 18290707. The next prime is 18290761. The reversal of 18290731 is 13709281.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 13709281 = 131 ⋅104651.

It is a cyclic number.

It is not a de Polignac number, because 18290731 - 2⁹ = 18290219 is a prime.

It is a super-2 number, since 2×18290731² = 669101681028722, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 18290693 and 18290702.

It is not an unprimeable number, because it can be changed into a prime (18290761) 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 3 ways as a sum of consecutive naturals, for example, 14460 + ... + 15673.

It is an arithmetic number, because the mean of its divisors is an integer number (4580368).

Almost surely, 2^18290731 is an apocalyptic number.

18290731 is a deficient number, since it is larger than the sum of its proper divisors (30741).

18290731 is an equidigital number, since it uses as much as digits as its factorization.

18290731 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30740.

The product of its (nonzero) digits is 3024, while the sum is 31.

The square root of 18290731 is about 4276.7664186860. The cubic root of 18290731 is about 263.4775931604.

The spelling of 18290731 in words is "eighteen million, two hundred ninety thousand, seven hundred thirty-one".