18278909287 has 2 divisors, whose sum is σ = 18278909288. Its totient is φ = 18278909286.

The previous prime is 18278909273. The next prime is 18278909323. The reversal of 18278909287 is 78290987281.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 18278909287 - 2²³ = 18270520679 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18278903287) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9139454643 + 9139454644.

It is an arithmetic number, because the mean of its divisors is an integer number (9139454644).

Almost surely, 2^18278909287 is an apocalyptic number.

18278909287 is a deficient number, since it is larger than the sum of its proper divisors (1).

18278909287 is an equidigital number, since it uses as much as digits as its factorization.

18278909287 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 8128512, while the sum is 61.

The spelling of 18278909287 in words is "eighteen billion, two hundred seventy-eight million, nine hundred nine thousand, two hundred eighty-seven".