64304005721 has 2 divisors, whose sum is σ = 64304005722. Its totient is φ = 64304005720.

The previous prime is 64304005709. The next prime is 64304005739. The reversal of 64304005721 is 12750040346.

64304005721 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 59895709696 + 4408296025 = 244736^2 + 66395^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-64304005721 is a prime.

It is not a weakly prime, because it can be changed into another prime (64304005021) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32152002860 + 32152002861.

It is an arithmetic number, because the mean of its divisors is an integer number (32152002861).

Almost surely, 2^64304005721 is an apocalyptic number.

It is an amenable number.

64304005721 is a deficient number, since it is larger than the sum of its proper divisors (1).

64304005721 is an equidigital number, since it uses as much as digits as its factorization.

64304005721 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 20160, while the sum is 32.

The spelling of 64304005721 in words is "sixty-four billion, three hundred four million, five thousand, seven hundred twenty-one".