1865489920 has 160 divisors (see below), whose sum is σ = 5381798400. Its totient is φ = 605822976.

The previous prime is 1865489893. The next prime is 1865489921. The reversal of 1865489920 is 299845681.

It is a tau number, because it is divible by the number of its divisors (160).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1865489921) 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 in 15 ways as a sum of consecutive naturals, for example, 337741 + ... + 343219.

It is an arithmetic number, because the mean of its divisors is an integer number (33636240).

Almost surely, 2^1865489920 is an apocalyptic number.

1865489920 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1865489920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2690899200).

1865489920 is an abundant number, since it is smaller than the sum of its proper divisors (3516308480).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1865489920 is an equidigital number, since it uses as much as digits as its factorization.

1865489920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5528 (or 5512 counting only the distinct ones).

The product of its (nonzero) digits is 1244160, while the sum is 52.

The square root of 1865489920 is about 43191.3176460270. The cubic root of 1865489920 is about 1231.0177136760.

The spelling of 1865489920 in words is "one billion, eight hundred sixty-five million, four hundred eighty-nine thousand, nine hundred twenty".