165810020 has 24 divisors (see below), whose sum is σ = 349312824. Its totient is φ = 66112256.

The previous prime is 165810011. The next prime is 165810067. The reversal of 165810020 is 20018561.

It can be written as a sum of positive squares in 4 ways, for example, as 4418404 + 161391616 = 2102^2 + 12704^2 .

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 6737 + ... + 19416.

It is an arithmetic number, because the mean of its divisors is an integer number (14554701).

Almost surely, 2^165810020 is an apocalyptic number.

165810020 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

165810020 is an abundant number, since it is smaller than the sum of its proper divisors (183502804).

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

165810020 is a wasteful number, since it uses less digits than its factorization.

165810020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26479 (or 26477 counting only the distinct ones).

The product of its (nonzero) digits is 480, while the sum is 23.

The square root of 165810020 is about 12876.7239622506. The cubic root of 165810020 is about 549.3767264648.

Adding to 165810020 its reverse (20018561), we get a palindrome (185828581).

The spelling of 165810020 in words is "one hundred sixty-five million, eight hundred ten thousand, twenty".