7236721 has 2 divisors, whose sum is σ = 7236722. Its totient is φ = 7236720.

The previous prime is 7236707. The next prime is 7236727. The reversal of 7236721 is 1276327.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 4223025 + 3013696 = 2055^2 + 1736^2 .

It is a cyclic number.

It is not a de Polignac number, because 7236721 - 2⁹ = 7236209 is a prime.

It is an alternating number because its digits alternate between odd and even.

It is a self number, because there is not a number n which added to its sum of digits gives 7236721.

It is not a weakly prime, because it can be changed into another prime (7236727) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3618360 + 3618361.

It is an arithmetic number, because the mean of its divisors is an integer number (3618361).

Almost surely, 2^7236721 is an apocalyptic number.

It is an amenable number.

7236721 is a deficient number, since it is larger than the sum of its proper divisors (1).

7236721 is an equidigital number, since it uses as much as digits as its factorization.

7236721 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3528, while the sum is 28.

The square root of 7236721 is about 2690.1154250329. The cubic root of 7236721 is about 193.4255957443.

The spelling of 7236721 in words is "seven million, two hundred thirty-six thousand, seven hundred twenty-one".