18458881478 has 4 divisors (see below), whose sum is σ = 27688322220. Its totient is φ = 9229440738.

The previous prime is 18458881439. The next prime is 18458881513. The reversal of 18458881478 is 87418885481.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 87418885481 = 221497 ⋅394673.

It is a self number, because there is not a number n which added to its sum of digits gives 18458881478.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4614720368 + ... + 4614720371.

It is an arithmetic number, because the mean of its divisors is an integer number (6922080555).

Almost surely, 2^18458881478 is an apocalyptic number.

18458881478 is a deficient number, since it is larger than the sum of its proper divisors (9229440742).

18458881478 is an equidigital number, since it uses as much as digits as its factorization.

18458881478 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9229440741.

The product of its digits is 18350080, while the sum is 62.

The spelling of 18458881478 in words is "eighteen billion, four hundred fifty-eight million, eight hundred eighty-one thousand, four hundred seventy-eight".