181749109920 has 384 divisors, whose sum is σ = 671870287872. Its totient is φ = 40431820800.

The previous prime is 181749109907. The next prime is 181749109957. The reversal of 181749109920 is 29901947181.

It is a happy number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 67638817 + ... + 67641503.

It is an arithmetic number, because the mean of its divisors is an integer number (1749662208).

Almost surely, 2^181749109920 is an apocalyptic number.

181749109920 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 181749109920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (335935143936).

181749109920 is an abundant number, since it is smaller than the sum of its proper divisors (490121177952).

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

181749109920 is a wasteful number, since it uses less digits than its factorization.

181749109920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3244 (or 3236 counting only the distinct ones).

The product of its (nonzero) digits is 326592, while the sum is 51.

The spelling of 181749109920 in words is "one hundred eighty-one billion, seven hundred forty-nine million, one hundred nine thousand, nine hundred twenty".