181856489472 has 624 divisors, whose sum is σ = 644378761920. Its totient is φ = 50498961408.

The previous prime is 181856489471. The next prime is 181856489483. The reversal of 181856489472 is 274984658181.

181856489472 is a `hidden beast` number, since 1 + 8 + 1 + 85 + 6 + 4 + 89 + 472 = 666.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (181856489471) by changing a digit.

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, 200502843 + ... + 200503749.

Almost surely, 2^181856489472 is an apocalyptic number.

181856489472 is a gapful number since it is divisible by the number (12) 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 181856489472, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (322189380960).

181856489472 is an abundant number, since it is smaller than the sum of its proper divisors (462522272448).

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

181856489472 is an equidigital number, since it uses as much as digits as its factorization.

181856489472 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 991 (or 956 counting only the distinct ones).

The product of its digits is 30965760, while the sum is 63.

The spelling of 181856489472 in words is "one hundred eighty-one billion, eight hundred fifty-six million, four hundred eighty-nine thousand, four hundred seventy-two".