181640992 has 48 divisors (see below), whose sum is σ = 395555832. Its totient is φ = 81561600.

The previous prime is 181640989. The next prime is 181641001. The reversal of 181640992 is 299046181.

181640992 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 160883856 + 20757136 = 12684^2 + 4556^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9492 + ... + 21292.

Almost surely, 2^181640992 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 181640992, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (197777916).

181640992 is an abundant number, since it is smaller than the sum of its proper divisors (213914840).

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

181640992 is a wasteful number, since it uses less digits than its factorization.

181640992 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11861 (or 11853 counting only the distinct ones).

The product of its (nonzero) digits is 31104, while the sum is 40.

The square root of 181640992 is about 13477.4252733970. The cubic root of 181640992 is about 566.3322434296.

The spelling of 181640992 in words is "one hundred eighty-one million, six hundred forty thousand, nine hundred ninety-two".