181997180497 has 4 divisors (see below), whose sum is σ = 198542378736. Its totient is φ = 165451982260.

The previous prime is 181997180479. The next prime is 181997180509. The reversal of 181997180497 is 794081799181.

181997180497 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 181997180497 - 2¹⁹ = 181996656209 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (181997180437) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8272599103 + ... + 8272599124.

It is an arithmetic number, because the mean of its divisors is an integer number (49635594684).

Almost surely, 2^181997180497 is an apocalyptic number.

It is an amenable number.

181997180497 is a deficient number, since it is larger than the sum of its proper divisors (16545198239).

181997180497 is a wasteful number, since it uses less digits than its factorization.

181997180497 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16545198238.

The product of its (nonzero) digits is 9144576, while the sum is 64.

The spelling of 181997180497 in words is "one hundred eighty-one billion, nine hundred ninety-seven million, one hundred eighty thousand, four hundred ninety-seven".