6181821520 has 160 divisors (see below), whose sum is σ = 17532592128. Its totient is φ = 1978712064.

The previous prime is 6181821497. The next prime is 6181821523. The reversal of 6181821520 is 251281816.

It is a super-2 number, since 2×6181821520² = 76429834610270220800, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (34).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6181821523) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1206484 + ... + 1211596.

Almost surely, 2^6181821520 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 6181821520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (8766296064).

6181821520 is an abundant number, since it is smaller than the sum of its proper divisors (11350770608).

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

6181821520 is a wasteful number, since it uses less digits than its factorization.

6181821520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5277 (or 5271 counting only the distinct ones).

The product of its (nonzero) digits is 7680, while the sum is 34.

The square root of 6181821520 is about 78624.5605393124. The cubic root of 6181821520 is about 1835.2933346495.

It can be divided in two parts, 61818 and 21520, that added together give a palindrome (83338).

The spelling of 6181821520 in words is "six billion, one hundred eighty-one million, eight hundred twenty-one thousand, five hundred twenty".