730210721 has 2 divisors, whose sum is σ = 730210722. Its totient is φ = 730210720.

The previous prime is 730210711. The next prime is 730210769. The reversal of 730210721 is 127012037.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 730080400 + 130321 = 27020^2 + 361^2 .

It is an emirp because it is prime and its reverse (127012037) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 730210721 - 2¹⁸ = 729948577 is a prime.

It is not a weakly prime, because it can be changed into another prime (730210711) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 365105360 + 365105361.

It is an arithmetic number, because the mean of its divisors is an integer number (365105361).

Almost surely, 2^730210721 is an apocalyptic number.

It is an amenable number.

730210721 is a deficient number, since it is larger than the sum of its proper divisors (1).

730210721 is an equidigital number, since it uses as much as digits as its factorization.

730210721 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 588, while the sum is 23.

The square root of 730210721 is about 27022.4114578992. The cubic root of 730210721 is about 900.4979635242.

Adding to 730210721 its reverse (127012037), we get a palindrome (857222758).

The spelling of 730210721 in words is "seven hundred thirty million, two hundred ten thousand, seven hundred twenty-one".