1305641861 has 2 divisors, whose sum is σ = 1305641862. Its totient is φ = 1305641860.

The previous prime is 1305641839. The next prime is 1305641863. The reversal of 1305641861 is 1681465031.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 840420100 + 465221761 = 28990^2 + 21569^2 .

It is a cyclic number.

It is not a de Polignac number, because 1305641861 - 2²² = 1301447557 is a prime.

It is a Sophie Germain prime.

Together with 1305641863, it forms a pair of twin primes.

It is a Chen prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1305641863) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 652820930 + 652820931.

It is an arithmetic number, because the mean of its divisors is an integer number (652820931).

Almost surely, 2^1305641861 is an apocalyptic number.

It is an amenable number.

1305641861 is a deficient number, since it is larger than the sum of its proper divisors (1).

1305641861 is an equidigital number, since it uses as much as digits as its factorization.

1305641861 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 17280, while the sum is 35.

The square root of 1305641861 is about 36133.6665867166. Note that the first 3 decimals coincide. The cubic root of 1305641861 is about 1092.9694473549.

The spelling of 1305641861 in words is "one billion, three hundred five million, six hundred forty-one thousand, eight hundred sixty-one".