18821333505 has 64 divisors (see below), whose sum is σ = 34367493888. Its totient is φ = 8713420800.

The previous prime is 18821333497. The next prime is 18821333507. The reversal of 18821333505 is 50533312881.

It is not a de Polignac number, because 18821333505 - 2³ = 18821333497 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is not an unprimeable number, because it can be changed into a prime (18821333507) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 6718105 + ... + 6720905.

It is an arithmetic number, because the mean of its divisors is an integer number (536992092).

Almost surely, 2^18821333505 is an apocalyptic number.

18821333505 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

18821333505 is a deficient number, since it is larger than the sum of its proper divisors (15546160383).

18821333505 is a wasteful number, since it uses less digits than its factorization.

18821333505 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4866.

The product of its (nonzero) digits is 86400, while the sum is 39.

The spelling of 18821333505 in words is "eighteen billion, eight hundred twenty-one million, three hundred thirty-three thousand, five hundred five".