18681653 has 2 divisors, whose sum is σ = 18681654. Its totient is φ = 18681652.

The previous prime is 18681647. The next prime is 18681661. The reversal of 18681653 is 35618681.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18472804 + 208849 = 4298^2 + 457^2 .

It is a cyclic number.

It is not a de Polignac number, because 18681653 - 2¹² = 18677557 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18681613) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9340826 + 9340827.

It is an arithmetic number, because the mean of its divisors is an integer number (9340827).

Almost surely, 2^18681653 is an apocalyptic number.

It is an amenable number.

18681653 is a deficient number, since it is larger than the sum of its proper divisors (1).

18681653 is an equidigital number, since it uses as much as digits as its factorization.

18681653 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 34560, while the sum is 38.

The square root of 18681653 is about 4322.2277820587. The cubic root of 18681653 is about 265.3414513914.

The spelling of 18681653 in words is "eighteen million, six hundred eighty-one thousand, six hundred fifty-three".