1865408489 has 12 divisors (see below), whose sum is σ = 2200531968. Its totient is φ = 1576398600.

The previous prime is 1865408471. The next prime is 1865408513. The reversal of 1865408489 is 9848045681.

It is a happy number.

It is not a de Polignac number, because 1865408489 - 2¹⁶ = 1865342953 is a prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 1865408489.

It is not an unprimeable number, because it can be changed into a prime (1865408459) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 264617 + ... + 271574.

It is an arithmetic number, because the mean of its divisors is an integer number (183377664).

Almost surely, 2^1865408489 is an apocalyptic number.

It is an amenable number.

1865408489 is a deficient number, since it is larger than the sum of its proper divisors (335123479).

1865408489 is an equidigital number, since it uses as much as digits as its factorization.

1865408489 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 536276 (or 536269 counting only the distinct ones).

The product of its (nonzero) digits is 2211840, while the sum is 53.

The square root of 1865408489 is about 43190.3749578537. The cubic root of 1865408489 is about 1230.9998015874. Note that the first 3 decimals are identical.

The spelling of 1865408489 in words is "one billion, eight hundred sixty-five million, four hundred eight thousand, four hundred eighty-nine".