7236821 has 2 divisors, whose sum is σ = 7236822. Its totient is φ = 7236820.

The previous prime is 7236811. The next prime is 7236829. The reversal of 7236821 is 1286327.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 6002500 + 1234321 = 2450^2 + 1111^2 .

It is a cyclic number.

It is not a de Polignac number, because 7236821 - 2¹⁰ = 7235797 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 (7236829) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3618410 + 3618411.

It is an arithmetic number, because the mean of its divisors is an integer number (3618411).

Almost surely, 2^7236821 is an apocalyptic number.

It is an amenable number.

7236821 is a deficient number, since it is larger than the sum of its proper divisors (1).

7236821 is an equidigital number, since it uses as much as digits as its factorization.

7236821 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4032, while the sum is 29.

The square root of 7236821 is about 2690.1340115318. The cubic root of 7236821 is about 193.4264866851.

The spelling of 7236821 in words is "seven million, two hundred thirty-six thousand, eight hundred twenty-one".