181471221072 has 160 divisors (see below), whose sum is σ = 530330342400. Its totient is φ = 59396450688.

The previous prime is 181471221037. The next prime is 181471221083. The reversal of 181471221072 is 270122174181.

181471221072 is a `hidden beast` number, since 1 + 81 + 471 + 2 + 2 + 107 + 2 = 666.

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

It is a congruent number.

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 31 ways as a sum of consecutive naturals, for example, 25051083 + ... + 25058325.

It is an arithmetic number, because the mean of its divisors is an integer number (3314564640).

Almost surely, 2^181471221072 is an apocalyptic number.

181471221072 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 181471221072, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (265165171200).

181471221072 is an abundant number, since it is smaller than the sum of its proper divisors (348859121328).

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

181471221072 is a wasteful number, since it uses less digits than its factorization.

181471221072 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8302 (or 8290 counting only the distinct ones).

The product of its (nonzero) digits is 12544, while the sum is 36.

The spelling of 181471221072 in words is "one hundred eighty-one billion, four hundred seventy-one million, two hundred twenty-one thousand, seventy-two".