18046821643 has 2 divisors, whose sum is σ = 18046821644. Its totient is φ = 18046821642.

The previous prime is 18046821589. The next prime is 18046821679. The reversal of 18046821643 is 34612864081.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 18046821643 - 2¹³ = 18046813451 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 18046821643.

It is not a weakly prime, because it can be changed into another prime (18046821943) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9023410821 + 9023410822.

It is an arithmetic number, because the mean of its divisors is an integer number (9023410822).

Almost surely, 2^18046821643 is an apocalyptic number.

18046821643 is a deficient number, since it is larger than the sum of its proper divisors (1).

18046821643 is an equidigital number, since it uses as much as digits as its factorization.

18046821643 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 221184, while the sum is 43.

The spelling of 18046821643 in words is "eighteen billion, forty-six million, eight hundred twenty-one thousand, six hundred forty-three".