18611840520 has 576 divisors, whose sum is σ = 76309899120. Its totient is φ = 3899363328.

The previous prime is 18611840491. The next prime is 18611840561. The reversal of 18611840520 is 2504811681.

18611840520 is a `hidden beast` number, since 1 + 86 + 1 + 18 + 40 + 520 = 666.

It can be written as a sum of positive squares in 8 ways, for example, as 6214799556 + 12397040964 = 78834^2 + 111342^2 .

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 (13) of ones.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 63521494 + ... + 63521786.

Almost surely, 2^18611840520 is an apocalyptic number.

18611840520 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 18611840520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (38154949560).

18611840520 is an abundant number, since it is smaller than the sum of its proper divisors (57698058600).

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

18611840520 is a wasteful number, since it uses less digits than its factorization.

18611840520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 614 (or 600 counting only the distinct ones).

The product of its (nonzero) digits is 15360, while the sum is 36.

The spelling of 18611840520 in words is "eighteen billion, six hundred eleven million, eight hundred forty thousand, five hundred twenty".