1645850520 has 96 divisors (see below), whose sum is σ = 5358618720. Its totient is φ = 438105600.

The previous prime is 1645850519. The next prime is 1645850527. The reversal of 1645850520 is 250585461.

1645850520 is a `hidden beast` number, since 1 + 645 + 8 + 5 + 0 + 5 + 2 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1645850527) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 212557 + ... + 220163.

It is an arithmetic number, because the mean of its divisors is an integer number (55818945).

Almost surely, 2^1645850520 is an apocalyptic number.

1645850520 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 1645850520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2679309360).

1645850520 is an abundant number, since it is smaller than the sum of its proper divisors (3712768200).

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

1645850520 is a wasteful number, since it uses less digits than its factorization.

1645850520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8225 (or 8218 counting only the distinct ones).

The product of its (nonzero) digits is 48000, while the sum is 36.

The square root of 1645850520 is about 40569.0833024361. The cubic root of 1645850520 is about 1180.6743536025.

It can be divided in two parts, 1645 and 850520, that added together give a triangular number (852165 = T₁₃₀₅).

The spelling of 1645850520 in words is "one billion, six hundred forty-five million, eight hundred fifty thousand, five hundred twenty".