1865286721 has 2 divisors, whose sum is σ = 1865286722. Its totient is φ = 1865286720.

The previous prime is 1865286713. The next prime is 1865286727. The reversal of 1865286721 is 1276825681.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1416694321 + 448592400 = 37639^2 + 21180^2 .

It is a cyclic number.

It is not a de Polignac number, because 1865286721 - 2³ = 1865286713 is a prime.

It is not a weakly prime, because it can be changed into another prime (1865286727) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 932643360 + 932643361.

It is an arithmetic number, because the mean of its divisors is an integer number (932643361).

Almost surely, 2^1865286721 is an apocalyptic number.

It is an amenable number.

1865286721 is a deficient number, since it is larger than the sum of its proper divisors (1).

1865286721 is an equidigital number, since it uses as much as digits as its factorization.

1865286721 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 322560, while the sum is 46.

The square root of 1865286721 is about 43188.9652689203. The cubic root of 1865286721 is about 1230.9730157393.

The spelling of 1865286721 in words is "one billion, eight hundred sixty-five million, two hundred eighty-six thousand, seven hundred twenty-one".