8993921 has 2 divisors, whose sum is σ = 8993922. Its totient is φ = 8993920.

The previous prime is 8993909. The next prime is 8993927. The reversal of 8993921 is 1293998.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 6225025 + 2768896 = 2495^2 + 1664^2 .

It is a cyclic number.

It is not a de Polignac number, because 8993921 - 2¹⁰ = 8992897 is a prime.

It is a super-2 number, since 2×8993921² = 161781229908482, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (8993927) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4496960 + 4496961.

It is an arithmetic number, because the mean of its divisors is an integer number (4496961).

Almost surely, 2^8993921 is an apocalyptic number.

It is an amenable number.

8993921 is a deficient number, since it is larger than the sum of its proper divisors (1).

8993921 is an equidigital number, since it uses as much as digits as its factorization.

8993921 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 34992, while the sum is 41.

The square root of 8993921 is about 2998.9866621911. The cubic root of 8993921 is about 207.9615390549.

The spelling of 8993921 in words is "eight million, nine hundred ninety-three thousand, nine hundred twenty-one".