18851538540 has 24 divisors (see below), whose sum is σ = 52784308080. Its totient is φ = 5027076928.

The previous prime is 18851538487. The next prime is 18851538581. The reversal of 18851538540 is 4583515881.

It is a self number, because there is not a number n which added to its sum of digits gives 18851538540.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 157096095 + ... + 157096214.

It is an arithmetic number, because the mean of its divisors is an integer number (2199346170).

Almost surely, 2^18851538540 is an apocalyptic number.

18851538540 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18851538540 is an abundant number, since it is smaller than the sum of its proper divisors (33932769540).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

18851538540 is a wasteful number, since it uses less digits than its factorization.

18851538540 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 314192321 (or 314192319 counting only the distinct ones).

The product of its (nonzero) digits is 768000, while the sum is 48.

The spelling of 18851538540 in words is "eighteen billion, eight hundred fifty-one million, five hundred thirty-eight thousand, five hundred forty".