1865920321 has 2 divisors, whose sum is σ = 1865920322. Its totient is φ = 1865920320.

The previous prime is 1865920313. The next prime is 1865920337. The reversal of 1865920321 is 1230295681.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1843500096 + 22420225 = 42936^2 + 4735^2 .

It is a cyclic number.

It is not a de Polignac number, because 1865920321 - 2³ = 1865920313 is a prime.

It is not a weakly prime, because it can be changed into another prime (1865920621) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 932960160 + 932960161.

It is an arithmetic number, because the mean of its divisors is an integer number (932960161).

Almost surely, 2^1865920321 is an apocalyptic number.

It is an amenable number.

1865920321 is a deficient number, since it is larger than the sum of its proper divisors (1).

1865920321 is an equidigital number, since it uses as much as digits as its factorization.

1865920321 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 25920, while the sum is 37.

The square root of 1865920321 is about 43196.2998531124. The cubic root of 1865920321 is about 1231.1123788016.

The spelling of 1865920321 in words is "one billion, eight hundred sixty-five million, nine hundred twenty thousand, three hundred twenty-one".