18697477 has 2 divisors, whose sum is σ = 18697478. Its totient is φ = 18697476.

The previous prime is 18697457. The next prime is 18697507. The reversal of 18697477 is 77479681.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 14753281 + 3944196 = 3841^2 + 1986^2 .

It is an emirp because it is prime and its reverse (77479681) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18697477 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 18697477.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18697447) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9348738 + 9348739.

It is an arithmetic number, because the mean of its divisors is an integer number (9348739).

Almost surely, 2^18697477 is an apocalyptic number.

It is an amenable number.

18697477 is a deficient number, since it is larger than the sum of its proper divisors (1).

18697477 is an equidigital number, since it uses as much as digits as its factorization.

18697477 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 592704, while the sum is 49.

The square root of 18697477 is about 4324.0579320819. The cubic root of 18697477 is about 265.4163480148.

The spelling of 18697477 in words is "eighteen million, six hundred ninety-seven thousand, four hundred seventy-seven".