1865065945021 has 2 divisors, whose sum is σ = 1865065945022. Its totient is φ = 1865065945020.

The previous prime is 1865065944971. The next prime is 1865065945079. The reversal of 1865065945021 is 1205495605681.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1820961324900 + 44104620121 = 1349430^2 + 210011^2 .

It is a cyclic number.

It is not a de Polignac number, because 1865065945021 - 2²⁵ = 1865032390589 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1865065945021.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1865065915021) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 932532972510 + 932532972511.

It is an arithmetic number, because the mean of its divisors is an integer number (932532972511).

Almost surely, 2^{1865065945021} is an apocalyptic number.

It is an amenable number.

1865065945021 is a deficient number, since it is larger than the sum of its proper divisors (1).

1865065945021 is an equidigital number, since it uses as much as digits as its factorization.

1865065945021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2592000, while the sum is 52.

The spelling of 1865065945021 in words is "one trillion, eight hundred sixty-five billion, sixty-five million, nine hundred forty-five thousand, twenty-one".