201217728 has 28 divisors (see below), whose sum is σ = 532389080. Its totient is φ = 67072512.

The previous prime is 201217727. The next prime is 201217759. The reversal of 201217728 is 827712102.

It is a happy number.

It is a super-2 number, since 2×201217728² = 80977148122963968, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 201217695 and 201217704.

It is not an unprimeable number, because it can be changed into a prime (201217727) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 523813 + ... + 524196.

Almost surely, 2^201217728 is an apocalyptic number.

It is an amenable number.

201217728 is an abundant number, since it is smaller than the sum of its proper divisors (331171352).

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

201217728 is a wasteful number, since it uses less digits than its factorization.

201217728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1048024 (or 1048014 counting only the distinct ones).

The product of its (nonzero) digits is 3136, while the sum is 30.

The square root of 201217728 is about 14185.1234749649. The cubic root of 201217728 is about 585.9880330078.

The spelling of 201217728 in words is "two hundred one million, two hundred seventeen thousand, seven hundred twenty-eight".