201221928 has 64 divisors (see below), whose sum is σ = 591840000. Its totient is φ = 63127296.

The previous prime is 201221921. The next prime is 201221929. The reversal of 201221928 is 829122102.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (201221921) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 23728 + ... + 31071.

It is an arithmetic number, because the mean of its divisors is an integer number (9247500).

Almost surely, 2^201221928 is an apocalyptic number.

It is an amenable number.

201221928 is an abundant number, since it is smaller than the sum of its proper divisors (390618072).

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

201221928 is a wasteful number, since it uses less digits than its factorization.

201221928 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 54831 (or 54821 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 27.

The square root of 201221928 is about 14185.2715166119. The cubic root of 201221928 is about 585.9921100717.

The spelling of 201221928 in words is "two hundred one million, two hundred twenty-one thousand, nine hundred twenty-eight".