9031218921 has 24 divisors (see below), whose sum is σ = 13600357056. Its totient is φ = 5769822240.

The previous prime is 9031218899. The next prime is 9031218949. The reversal of 9031218921 is 1298121309.

It is not a de Polignac number, because 9031218921 - 2⁹ = 9031218409 is a prime.

It is not an unprimeable number, because it can be changed into a prime (9031218991) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 199645 + ... + 240666.

It is an arithmetic number, because the mean of its divisors is an integer number (566681544).

Almost surely, 2^9031218921 is an apocalyptic number.

It is an amenable number.

9031218921 is a deficient number, since it is larger than the sum of its proper divisors (4569138135).

9031218921 is a wasteful number, since it uses less digits than its factorization.

9031218921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 440413 (or 440410 counting only the distinct ones).

The product of its (nonzero) digits is 7776, while the sum is 36.

The square root of 9031218921 is about 95032.7255265259. The cubic root of 9031218921 is about 2082.4861575691.

The spelling of 9031218921 in words is "nine billion, thirty-one million, two hundred eighteen thousand, nine hundred twenty-one".