18630397 has 2 divisors, whose sum is σ = 18630398. Its totient is φ = 18630396.

The previous prime is 18630379. The next prime is 18630449. The reversal of 18630397 is 79303681.

Together with previous prime (18630379) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18481401 + 148996 = 4299^2 + 386^2 .

It is a cyclic number.

It is not a de Polignac number, because 18630397 - 2²³ = 10241789 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18630347) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9315198 + 9315199.

It is an arithmetic number, because the mean of its divisors is an integer number (9315199).

Almost surely, 2^18630397 is an apocalyptic number.

It is an amenable number.

18630397 is a deficient number, since it is larger than the sum of its proper divisors (1).

18630397 is an equidigital number, since it uses as much as digits as its factorization.

18630397 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 27216, while the sum is 37.

The square root of 18630397 is about 4316.2943597489. The cubic root of 18630397 is about 265.0985607037.

The spelling of 18630397 in words is "eighteen million, six hundred thirty thousand, three hundred ninety-seven".