181916442 has 20 divisors (see below), whose sum is σ = 407627946. Its totient is φ = 60638760.

The previous prime is 181916377. The next prime is 181916459. The reversal of 181916442 is 244619181.

181916442 is a `hidden beast` number, since 1 + 8 + 1 + 9 + 1 + 644 + 2 = 666.

It can be written as a sum of positive squares in only one way, i.e., 180069561 + 1846881 = 13419^2 + 1359^2 .

It is a junction number, because it is equal to n+sod(n) for n = 181916397 and 181916406.

It is an unprimeable number.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 561309 + ... + 561632.

Almost surely, 2^181916442 is an apocalyptic number.

181916442 is an abundant number, since it is smaller than the sum of its proper divisors (225711504).

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

181916442 is a wasteful number, since it uses less digits than its factorization.

181916442 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1122955 (or 1122946 counting only the distinct ones).

The product of its digits is 13824, while the sum is 36.

The square root of 181916442 is about 13487.6403421799. The cubic root of 181916442 is about 566.6183708936.

The spelling of 181916442 in words is "one hundred eighty-one million, nine hundred sixteen thousand, four hundred forty-two".