261982319 has 2 divisors, whose sum is σ = 261982320. Its totient is φ = 261982318.

The previous prime is 261982283. The next prime is 261982363. The reversal of 261982319 is 913289162.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-261982319 is a prime.

It is a super-2 number, since 2×261982319² = 137269470937235522, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (261982219) 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, 130991159 + 130991160.

It is an arithmetic number, because the mean of its divisors is an integer number (130991160).

Almost surely, 2^261982319 is an apocalyptic number.

261982319 is a deficient number, since it is larger than the sum of its proper divisors (1).

261982319 is an equidigital number, since it uses as much as digits as its factorization.

261982319 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 46656, while the sum is 41.

The square root of 261982319 is about 16185.8678791099. The cubic root of 261982319 is about 639.8683966056.

The spelling of 261982319 in words is "two hundred sixty-one million, nine hundred eighty-two thousand, three hundred nineteen".