18613897 has 2 divisors, whose sum is σ = 18613898. Its totient is φ = 18613896.

The previous prime is 18613891. The next prime is 18613913. The reversal of 18613897 is 79831681.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18481401 + 132496 = 4299^2 + 364^2 .

It is a cyclic number.

It is not a de Polignac number, because 18613897 - 2⁷ = 18613769 is a prime.

It is not a weakly prime, because it can be changed into another prime (18613891) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9306948 + 9306949.

It is an arithmetic number, because the mean of its divisors is an integer number (9306949).

Almost surely, 2^18613897 is an apocalyptic number.

It is an amenable number.

18613897 is a deficient number, since it is larger than the sum of its proper divisors (1).

18613897 is an equidigital number, since it uses as much as digits as its factorization.

18613897 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 72576, while the sum is 43.

The square root of 18613897 is about 4314.3825745986. The cubic root of 18613897 is about 265.0202761274.

The spelling of 18613897 in words is "eighteen million, six hundred thirteen thousand, eight hundred ninety-seven".