18811450447 has 2 divisors, whose sum is σ = 18811450448. Its totient is φ = 18811450446.

The previous prime is 18811450429. The next prime is 18811450457. The reversal of 18811450447 is 74405411881.

It is a strong prime.

It is an emirp because it is prime and its reverse (74405411881) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 18811450447 - 2¹⁹ = 18810926159 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18811450457) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9405725223 + 9405725224.

It is an arithmetic number, because the mean of its divisors is an integer number (9405725224).

Almost surely, 2^18811450447 is an apocalyptic number.

18811450447 is a deficient number, since it is larger than the sum of its proper divisors (1).

18811450447 is an equidigital number, since it uses as much as digits as its factorization.

18811450447 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 143360, while the sum is 43.

The spelling of 18811450447 in words is "eighteen billion, eight hundred eleven million, four hundred fifty thousand, four hundred forty-seven".