7974821 has 2 divisors, whose sum is σ = 7974822. Its totient is φ = 7974820.

The previous prime is 7974803. The next prime is 7974829. The reversal of 7974821 is 1284797.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 6558721 + 1416100 = 2561^2 + 1190^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-7974821 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (7974829) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3987410 + 3987411.

It is an arithmetic number, because the mean of its divisors is an integer number (3987411).

Almost surely, 2^7974821 is an apocalyptic number.

It is an amenable number.

7974821 is a deficient number, since it is larger than the sum of its proper divisors (1).

7974821 is an equidigital number, since it uses as much as digits as its factorization.

7974821 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 28224, while the sum is 38.

The square root of 7974821 is about 2823.9725565239. The cubic root of 7974821 is about 199.7899544816.

The spelling of 7974821 in words is "seven million, nine hundred seventy-four thousand, eight hundred twenty-one".