181725159989 has 2 divisors, whose sum is σ = 181725159990. Its totient is φ = 181725159988.

The previous prime is 181725159961. The next prime is 181725159991. The reversal of 181725159989 is 989951527181.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 117504984100 + 64220175889 = 342790^2 + 253417^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-181725159989 is a prime.

Together with 181725159991, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (181725159949) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 90862579994 + 90862579995.

It is an arithmetic number, because the mean of its divisors is an integer number (90862579995).

Almost surely, 2^181725159989 is an apocalyptic number.

It is an amenable number.

181725159989 is a deficient number, since it is larger than the sum of its proper divisors (1).

181725159989 is an equidigital number, since it uses as much as digits as its factorization.

181725159989 is an evil number, because the sum of its binary digits is even.

The product of its digits is 16329600, while the sum is 65.

The spelling of 181725159989 in words is "one hundred eighty-one billion, seven hundred twenty-five million, one hundred fifty-nine thousand, nine hundred eighty-nine".