181994325120 has 224 divisors, whose sum is σ = 652323538620. Its totient is φ = 48531695616.

The previous prime is 181994325103. The next prime is 181994325127. The reversal of 181994325120 is 21523499181.

181994325120 is a `hidden beast` number, since 1 + 8 + 1 + 99 + 43 + 2 + 512 + 0 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 161237583936 + 20756741184 = 401544^2 + 144072^2 .

It is a Harshad number since it is a multiple of its sum of digits (45).

It is not an unprimeable number, because it can be changed into a prime (181994325127) by changing a digit.

It is a polite number, since it can be written in 27 ways as a sum of consecutive naturals, for example, 271522 + ... + 661598.

Almost surely, 2^181994325120 is an apocalyptic number.

181994325120 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 181994325120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (326161769310).

181994325120 is an abundant number, since it is smaller than the sum of its proper divisors (470329213500).

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

181994325120 is an frugal number, since it uses more digits than its factorization.

181994325120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 390114 (or 390087 counting only the distinct ones).

The product of its (nonzero) digits is 155520, while the sum is 45.

The spelling of 181994325120 in words is "one hundred eighty-one billion, nine hundred ninety-four million, three hundred twenty-five thousand, one hundred twenty".