181912225 has 24 divisors (see below), whose sum is σ = 246769920. Its totient is φ = 131928000.

The previous prime is 181912207. The next prime is 181912229. The reversal of 181912225 is 522219181.

181912225 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 181912225 - 2²¹ = 179815073 is a prime.

It is not an unprimeable number, because it can be changed into a prime (181912229) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 131035 + ... + 132415.

It is an arithmetic number, because the mean of its divisors is an integer number (10282080).

Almost surely, 2^181912225 is an apocalyptic number.

It is an amenable number.

181912225 is a deficient number, since it is larger than the sum of its proper divisors (64857695).

181912225 is a wasteful number, since it uses less digits than its factorization.

181912225 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1881 (or 1876 counting only the distinct ones).

The product of its digits is 2880, while the sum is 31.

The square root of 181912225 is about 13487.4840129655. The cubic root of 181912225 is about 566.6139926048.

The spelling of 181912225 in words is "one hundred eighty-one million, nine hundred twelve thousand, two hundred twenty-five".