721340773 has 2 divisors, whose sum is σ = 721340774. Its totient is φ = 721340772.

The previous prime is 721340761. The next prime is 721340777. The reversal of 721340773 is 377043127.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 582643044 + 138697729 = 24138^2 + 11777^2 .

It is a cyclic number.

It is not a de Polignac number, because 721340773 - 2¹³ = 721332581 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (721340777) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 360670386 + 360670387.

It is an arithmetic number, because the mean of its divisors is an integer number (360670387).

Almost surely, 2^721340773 is an apocalyptic number.

It is an amenable number.

721340773 is a deficient number, since it is larger than the sum of its proper divisors (1).

721340773 is an equidigital number, since it uses as much as digits as its factorization.

721340773 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 24696, while the sum is 34.

The square root of 721340773 is about 26857.7879394413. The cubic root of 721340773 is about 896.8369512249.

The spelling of 721340773 in words is "seven hundred twenty-one million, three hundred forty thousand, seven hundred seventy-three".