201605220 has 48 divisors (see below), whose sum is σ = 627217920. Its totient is φ = 53761248.

The previous prime is 201605213. The next prime is 201605249. The reversal of 201605220 is 22506102.

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 = 201605193 and 201605202.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 186132 + ... + 187211.

It is an arithmetic number, because the mean of its divisors is an integer number (13067040).

Almost surely, 2^201605220 is an apocalyptic number.

201605220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

201605220 is an abundant number, since it is smaller than the sum of its proper divisors (425612700).

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

201605220 is a wasteful number, since it uses less digits than its factorization.

201605220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 373361 (or 373353 counting only the distinct ones).

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

The square root of 201605220 is about 14198.7752992996. The cubic root of 201605220 is about 586.3639443432.

The spelling of 201605220 in words is "two hundred one million, six hundred five thousand, two hundred twenty".