18328997 has 2 divisors, whose sum is σ = 18328998. Its totient is φ = 18328996.

The previous prime is 18328991. The next prime is 18329011. The reversal of 18328997 is 79982381.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 16654561 + 1674436 = 4081^2 + 1294^2 .

It is a cyclic number.

It is not a de Polignac number, because 18328997 - 2¹⁰ = 18327973 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18328991) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9164498 + 9164499.

It is an arithmetic number, because the mean of its divisors is an integer number (9164499).

Almost surely, 2^18328997 is an apocalyptic number.

It is an amenable number.

18328997 is a deficient number, since it is larger than the sum of its proper divisors (1).

18328997 is an equidigital number, since it uses as much as digits as its factorization.

18328997 is an evil number, because the sum of its binary digits is even.

The product of its digits is 217728, while the sum is 47.

The square root of 18328997 is about 4281.2377883038. The cubic root of 18328997 is about 263.6612054817.

The spelling of 18328997 in words is "eighteen million, three hundred twenty-eight thousand, nine hundred ninety-seven".