165220020 has 192 divisors, whose sum is σ = 594316800. Its totient is φ = 37324800.

The previous prime is 165220009. The next prime is 165220021. The reversal of 165220020 is 20022561.

165220020 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 165219975 and 165220002.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (165220021) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 411820 + ... + 412220.

It is an arithmetic number, because the mean of its divisors is an integer number (3095400).

Almost surely, 2^165220020 is an apocalyptic number.

165220020 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 165220020, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (297158400).

165220020 is an abundant number, since it is smaller than the sum of its proper divisors (429096780).

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

165220020 is a wasteful number, since it uses less digits than its factorization.

165220020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 535 (or 527 counting only the distinct ones).

The product of its (nonzero) digits is 240, while the sum is 18.

The square root of 165220020 is about 12853.7939924366. The cubic root of 165220020 is about 548.7243383029.

Adding to 165220020 its reverse (20022561), we get a palindrome (185242581).

The spelling of 165220020 in words is "one hundred sixty-five million, two hundred twenty thousand, twenty".