163331261 has 2 divisors, whose sum is σ = 163331262. Its totient is φ = 163331260.

The previous prime is 163331237. The next prime is 163331297. The reversal of 163331261 is 162133361.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 160022500 + 3308761 = 12650^2 + 1819^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-163331261 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 163331261.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (163331761) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 81665630 + 81665631.

It is an arithmetic number, because the mean of its divisors is an integer number (81665631).

Almost surely, 2^163331261 is an apocalyptic number.

It is an amenable number.

163331261 is a deficient number, since it is larger than the sum of its proper divisors (1).

163331261 is an equidigital number, since it uses as much as digits as its factorization.

163331261 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1944, while the sum is 26.

The square root of 163331261 is about 12780.1119322172. Note that the first 3 decimals coincide. The cubic root of 163331261 is about 546.6253540976.

The spelling of 163331261 in words is "one hundred sixty-three million, three hundred thirty-one thousand, two hundred sixty-one".