9901212 has 12 divisors (see below), whose sum is σ = 23102856. Its totient is φ = 3300400.

The previous prime is 9901211. The next prime is 9901219. The reversal of 9901212 is 2121099.

It is a tau number, because it is divible by the number of its divisors (12).

It is a Smith number, since the sum of its digits (24) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9901211) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 412539 + ... + 412562.

It is an arithmetic number, because the mean of its divisors is an integer number (1925238).

Almost surely, 2^9901212 is an apocalyptic number.

It is an amenable number.

9901212 is an abundant number, since it is smaller than the sum of its proper divisors (13201644).

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

9901212 is a wasteful number, since it uses less digits than its factorization.

9901212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 825108 (or 825106 counting only the distinct ones).

The product of its (nonzero) digits is 324, while the sum is 24.

The square root of 9901212 is about 3146.6191380591. The cubic root of 9901212 is about 214.7316789745.

The spelling of 9901212 in words is "nine million, nine hundred one thousand, two hundred twelve".