4356721 has 2 divisors, whose sum is σ = 4356722. Its totient is φ = 4356720.

The previous prime is 4356697. The next prime is 4356727. The reversal of 4356721 is 1276534.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 2283121 + 2073600 = 1511^2 + 1440^2 .

It is a cyclic number.

It is not a de Polignac number, because 4356721 - 2⁵ = 4356689 is a prime.

It is an Ulam number.

It is a self number, because there is not a number n which added to its sum of digits gives 4356721.

It is not a weakly prime, because it can be changed into another prime (4356727) 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, 2178360 + 2178361.

It is an arithmetic number, because the mean of its divisors is an integer number (2178361).

Almost surely, 2^4356721 is an apocalyptic number.

It is an amenable number.

4356721 is a deficient number, since it is larger than the sum of its proper divisors (1).

4356721 is an equidigital number, since it uses as much as digits as its factorization.

4356721 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 5040, while the sum is 28.

The square root of 4356721 is about 2087.2759760032. The cubic root of 4356721 is about 163.3252191813.

The spelling of 4356721 in words is "four million, three hundred fifty-six thousand, seven hundred twenty-one".