2861390261 has 2 divisors, whose sum is σ = 2861390262. Its totient is φ = 2861390260.

The previous prime is 2861390249. The next prime is 2861390263. The reversal of 2861390261 is 1620931682.

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., 2465619025 + 395771236 = 49655^2 + 19894^2 .

It is a cyclic number.

It is not a de Polignac number, because 2861390261 - 2¹⁴ = 2861373877 is a prime.

Together with 2861390263, 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 (2861390263) 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, 1430695130 + 1430695131.

It is an arithmetic number, because the mean of its divisors is an integer number (1430695131).

Almost surely, 2^2861390261 is an apocalyptic number.

It is an amenable number.

2861390261 is a deficient number, since it is larger than the sum of its proper divisors (1).

2861390261 is an equidigital number, since it uses as much as digits as its factorization.

2861390261 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 31104, while the sum is 38.

The square root of 2861390261 is about 53491.9644526166. The cubic root of 2861390261 is about 1419.6862133146.

The spelling of 2861390261 in words is "two billion, eight hundred sixty-one million, three hundred ninety thousand, two hundred sixty-one".