9968921 has 4 divisors (see below), whose sum is σ = 9983844. Its totient is φ = 9954000.

The previous prime is 9968911. The next prime is 9968927. The reversal of 9968921 is 1298699.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 7778521 + 2190400 = 2789^2 + 1480^2 .

It is a cyclic number.

It is not a de Polignac number, because 9968921 - 2⁶ = 9968857 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (9968927) 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, 6410 + ... + 7811.

It is an arithmetic number, because the mean of its divisors is an integer number (2495961).

Almost surely, 2^9968921 is an apocalyptic number.

It is an amenable number.

9968921 is a deficient number, since it is larger than the sum of its proper divisors (14923).

9968921 is a wasteful number, since it uses less digits than its factorization.

9968921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14922.

The product of its digits is 69984, while the sum is 44.

The square root of 9968921 is about 3157.3598147820. The cubic root of 9968921 is about 215.2200451310.

The spelling of 9968921 in words is "nine million, nine hundred sixty-eight thousand, nine hundred twenty-one".