181355217083820 has 72 divisors (see below), whose sum is σ = 592427042481456. Its totient is φ = 44641284204672.

The previous prime is 181355217083801. The next prime is 181355217083863. The reversal of 181355217083820 is 28380712553181.

It is a happy number.

181355217083820 is a `hidden beast` number, since 1 + 8 + 1 + 3 + 552 + 1 + 7 + 0 + 8 + 3 + 82 + 0 = 666.

181355217083820 is digitally balanced in base 2 and base 4, because in such bases it contains all the possibile digits an equal number of times.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 38751112422 + ... + 38751117101.

It is an arithmetic number, because the mean of its divisors is an integer number (8228153367798).

Almost surely, 2^{181355217083820} is an apocalyptic number.

181355217083820 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

181355217083820 is an abundant number, since it is smaller than the sum of its proper divisors (411071825397636).

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

181355217083820 is a wasteful number, since it uses less digits than its factorization.

181355217083820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 77502229551 (or 77502229546 counting only the distinct ones).

The product of its (nonzero) digits is 3225600, while the sum is 54.

The spelling of 181355217083820 in words is "one hundred eighty-one trillion, three hundred fifty-five billion, two hundred seventeen million, eighty-three thousand, eight hundred twenty".