18816473491 has 2 divisors, whose sum is σ = 18816473492. Its totient is φ = 18816473490.

The previous prime is 18816473449. The next prime is 18816473537. The reversal of 18816473491 is 19437461881.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 18816473491 - 2⁷ = 18816473363 is a prime.

It is not a weakly prime, because it can be changed into another prime (18816473191) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9408236745 + 9408236746.

It is an arithmetic number, because the mean of its divisors is an integer number (9408236746).

Almost surely, 2^18816473491 is an apocalyptic number.

18816473491 is a deficient number, since it is larger than the sum of its proper divisors (1).

18816473491 is an equidigital number, since it uses as much as digits as its factorization.

18816473491 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1161216, while the sum is 52.

The spelling of 18816473491 in words is "eighteen billion, eight hundred sixteen million, four hundred seventy-three thousand, four hundred ninety-one".