9447921 has 40 divisors (see below), whose sum is σ = 16998080. Its totient is φ = 5108832.

The previous prime is 9447887. The next prime is 9447943. The reversal of 9447921 is 1297449.

It is not a de Polignac number, because 9447921 - 2⁶ = 9447857 is a prime.

It is a super-2 number, since 2×9447921² = 178526422444482, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (9447521) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 10335 + ... + 11211.

It is an arithmetic number, because the mean of its divisors is an integer number (424952).

Almost surely, 2^9447921 is an apocalyptic number.

It is an amenable number.

9447921 is a deficient number, since it is larger than the sum of its proper divisors (7550159).

9447921 is a wasteful number, since it uses less digits than its factorization.

9447921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 915 (or 906 counting only the distinct ones).

The product of its digits is 18144, while the sum is 36.

The square root of 9447921 is about 3073.7470618123. The cubic root of 9447921 is about 211.4034567676.

The spelling of 9447921 in words is "nine million, four hundred forty-seven thousand, nine hundred twenty-one".