1800165840 has 240 divisors, whose sum is σ = 6368967360. Its totient is φ = 417105920.

The previous prime is 1800165833. The next prime is 1800165841. The reversal of 1800165840 is 485610081.

It is a tau number, because it is divible by the number of its divisors (240).

It is a Harshad number since it is a multiple of its sum of digits (33).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1800165841) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1395916 + ... + 1397204.

It is an arithmetic number, because the mean of its divisors is an integer number (26537364).

Almost surely, 2^1800165840 is an apocalyptic number.

1800165840 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 1800165840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3184483680).

1800165840 is an abundant number, since it is smaller than the sum of its proper divisors (4568801520).

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

1800165840 is a wasteful number, since it uses less digits than its factorization.

1800165840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1362 (or 1333 counting only the distinct ones).

The product of its (nonzero) digits is 7680, while the sum is 33.

The square root of 1800165840 is about 42428.3612693208. The cubic root of 1800165840 is about 1216.4777562037.

The spelling of 1800165840 in words is "one billion, eight hundred million, one hundred sixty-five thousand, eight hundred forty".