9897729 has 12 divisors (see below), whose sum is σ = 13671216. Its totient is φ = 6369328.

The previous prime is 9897703. The next prime is 9897743. The reversal of 9897729 is 9277989.

It is a happy number.

9897729 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 9897729 - 2⁸ = 9897473 is a prime.

It is a Curzon number.

9897729 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (9897749) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 562 + ... + 4484.

It is an arithmetic number, because the mean of its divisors is an integer number (1139268).

Almost surely, 2^9897729 is an apocalyptic number.

9897729 is the 1682-nd nonagonal number.

It is an amenable number.

9897729 is a deficient number, since it is larger than the sum of its proper divisors (3773487).

9897729 is a wasteful number, since it uses less digits than its factorization.

9897729 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3984 (or 3955 counting only the distinct ones).

The product of its digits is 571536, while the sum is 51.

The square root of 9897729 is about 3146.0656382218. The cubic root of 9897729 is about 214.7064969344.

The spelling of 9897729 in words is "nine million, eight hundred ninety-seven thousand, seven hundred twenty-nine".