18227081 has 2 divisors, whose sum is σ = 18227082. Its totient is φ = 18227080.

The previous prime is 18227003. The next prime is 18227087. The reversal of 18227081 is 18072281.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 13987600 + 4239481 = 3740^2 + 2059^2 .

It is an emirp because it is prime and its reverse (18072281) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18227081 is a prime.

It is a super-2 number, since 2×18227081² = 664452963561122, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (18227087) by changing a digit.

It is a good prime.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9113540 + 9113541.

It is an arithmetic number, because the mean of its divisors is an integer number (9113541).

Almost surely, 2^18227081 is an apocalyptic number.

It is an amenable number.

18227081 is a deficient number, since it is larger than the sum of its proper divisors (1).

18227081 is an equidigital number, since it uses as much as digits as its factorization.

18227081 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1792, while the sum is 29.

The square root of 18227081 is about 4269.3185638928. The cubic root of 18227081 is about 263.1716123228.

The spelling of 18227081 in words is "eighteen million, two hundred twenty-seven thousand, eighty-one".