8971421 has 2 divisors, whose sum is σ = 8971422. Its totient is φ = 8971420.

The previous prime is 8971399. The next prime is 8971441. The reversal of 8971421 is 1241798.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 8916196 + 55225 = 2986^2 + 235^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-8971421 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (8971441) 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 as a sum of consecutive naturals, namely, 4485710 + 4485711.

It is an arithmetic number, because the mean of its divisors is an integer number (4485711).

Almost surely, 2^8971421 is an apocalyptic number.

It is an amenable number.

8971421 is a deficient number, since it is larger than the sum of its proper divisors (1).

8971421 is an equidigital number, since it uses as much as digits as its factorization.

8971421 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 4032, while the sum is 32.

The square root of 8971421 is about 2995.2330460250. The cubic root of 8971421 is about 207.7879758235.

The spelling of 8971421 in words is "eight million, nine hundred seventy-one thousand, four hundred twenty-one".