181997180479 has 2 divisors, whose sum is σ = 181997180480. Its totient is φ = 181997180478.

The previous prime is 181997180473. The next prime is 181997180509. The reversal of 181997180479 is 974081799181.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 181997180479 - 2³ = 181997180471 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 181997180479.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (181997180471) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 90998590239 + 90998590240.

It is an arithmetic number, because the mean of its divisors is an integer number (90998590240).

Almost surely, 2^181997180479 is an apocalyptic number.

181997180479 is a deficient number, since it is larger than the sum of its proper divisors (1).

181997180479 is an equidigital number, since it uses as much as digits as its factorization.

181997180479 is an evil number, because the sum of its binary digits is even.

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

The spelling of 181997180479 in words is "one hundred eighty-one billion, nine hundred ninety-seven million, one hundred eighty thousand, four hundred seventy-nine".