18538247461 has 2 divisors, whose sum is σ = 18538247462. Its totient is φ = 18538247460.

The previous prime is 18538247449. The next prime is 18538247489. The reversal of 18538247461 is 16474283581.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 13550356836 + 4987890625 = 116406^2 + 70625^2 .

It is a cyclic number.

It is not a de Polignac number, because 18538247461 - 2²⁵ = 18504693029 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18538247401) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9269123730 + 9269123731.

It is an arithmetic number, because the mean of its divisors is an integer number (9269123731).

Almost surely, 2^18538247461 is an apocalyptic number.

It is an amenable number.

18538247461 is a deficient number, since it is larger than the sum of its proper divisors (1).

18538247461 is an equidigital number, since it uses as much as digits as its factorization.

18538247461 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1290240, while the sum is 49.

The spelling of 18538247461 in words is "eighteen billion, five hundred thirty-eight million, two hundred forty-seven thousand, four hundred sixty-one".