18535541220 has 144 divisors (see below), whose sum is σ = 64430446080. Its totient is φ = 4225229568.

The previous prime is 18535541203. The next prime is 18535541239. The reversal of 18535541220 is 2214553581.

18535541220 is a `hidden beast` number, since 1 + 85 + 3 + 554 + 1 + 2 + 20 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

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 47 ways as a sum of consecutive naturals, for example, 450261 + ... + 489699.

Almost surely, 2^18535541220 is an apocalyptic number.

18535541220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18535541220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32215223040).

18535541220 is an abundant number, since it is smaller than the sum of its proper divisors (45894904860).

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

18535541220 is a wasteful number, since it uses less digits than its factorization.

18535541220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 39834 (or 39829 counting only the distinct ones).

The product of its (nonzero) digits is 48000, while the sum is 36.

The spelling of 18535541220 in words is "eighteen billion, five hundred thirty-five million, five hundred forty-one thousand, two hundred twenty".