181949391443 has 8 divisors (see below), whose sum is σ = 192664162512. Its totient is φ = 171235938816.

The previous prime is 181949391439. The next prime is 181949391451. The reversal of 181949391443 is 344193949181.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 181949391443 - 2² = 181949391439 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (181949391433) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 38105 + ... + 604442.

It is an arithmetic number, because the mean of its divisors is an integer number (24083020314).

Almost surely, 2^181949391443 is an apocalyptic number.

181949391443 is a deficient number, since it is larger than the sum of its proper divisors (10714771069).

181949391443 is a wasteful number, since it uses less digits than its factorization.

181949391443 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 659221.

The product of its digits is 3359232, while the sum is 56.

The spelling of 181949391443 in words is "one hundred eighty-one billion, nine hundred forty-nine million, three hundred ninety-one thousand, four hundred forty-three".