7766321 has 2 divisors, whose sum is σ = 7766322. Its totient is φ = 7766320.

The previous prime is 7766309. The next prime is 7766323. The reversal of 7766321 is 1236677.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 5125696 + 2640625 = 2264^2 + 1625^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-7766321 is a prime.

Together with 7766323, it forms a pair of twin primes.

It is a Chen prime.

It is a nialpdrome in base 10.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (7766323) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3883160 + 3883161.

It is an arithmetic number, because the mean of its divisors is an integer number (3883161).

Almost surely, 2^7766321 is an apocalyptic number.

It is an amenable number.

7766321 is a deficient number, since it is larger than the sum of its proper divisors (1).

7766321 is an equidigital number, since it uses as much as digits as its factorization.

7766321 is an evil number, because the sum of its binary digits is even.

The product of its digits is 10584, while the sum is 32.

The square root of 7766321 is about 2786.8119778701. The cubic root of 7766321 is about 198.0334008204.

The spelling of 7766321 in words is "seven million, seven hundred sixty-six thousand, three hundred twenty-one".