18423390487 has 4 divisors (see below), whose sum is σ = 18427208896. Its totient is φ = 18419572080.

The previous prime is 18423390449. The next prime is 18423390497. The reversal of 18423390487 is 78409332481.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 18423390487 - 2¹⁹ = 18422866199 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 18423390487.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18423390497) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1901958 + ... + 1911619.

It is an arithmetic number, because the mean of its divisors is an integer number (4606802224).

Almost surely, 2^18423390487 is an apocalyptic number.

18423390487 is a deficient number, since it is larger than the sum of its proper divisors (3818409).

18423390487 is an equidigital number, since it uses as much as digits as its factorization.

18423390487 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3818408.

The product of its (nonzero) digits is 1161216, while the sum is 49.

The spelling of 18423390487 in words is "eighteen billion, four hundred twenty-three million, three hundred ninety thousand, four hundred eighty-seven".