181860641 has 2 divisors, whose sum is σ = 181860642. Its totient is φ = 181860640.

The previous prime is 181860629. The next prime is 181860643. The reversal of 181860641 is 146068181.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 137358400 + 44502241 = 11720^2 + 6671^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-181860641 is a prime.

Together with 181860643, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (181860643) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 90930320 + 90930321.

It is an arithmetic number, because the mean of its divisors is an integer number (90930321).

Almost surely, 2^181860641 is an apocalyptic number.

It is an amenable number.

181860641 is a deficient number, since it is larger than the sum of its proper divisors (1).

181860641 is an equidigital number, since it uses as much as digits as its factorization.

181860641 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 9216, while the sum is 35.

The square root of 181860641 is about 13485.5715859581. The cubic root of 181860641 is about 566.5604301806.

The spelling of 181860641 in words is "one hundred eighty-one million, eight hundred sixty thousand, six hundred forty-one".