721601059909 has 2 divisors, whose sum is σ = 721601059910. Its totient is φ = 721601059908.

The previous prime is 721601059889. The next prime is 721601059931. The reversal of 721601059909 is 909950106127.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 702993371809 + 18607688100 = 838447^2 + 136410^2 .

It is a cyclic number.

It is not a de Polignac number, because 721601059909 - 2²³ = 721592671301 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (721601059939) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 360800529954 + 360800529955.

It is an arithmetic number, because the mean of its divisors is an integer number (360800529955).

Almost surely, 2^721601059909 is an apocalyptic number.

It is an amenable number.

721601059909 is a deficient number, since it is larger than the sum of its proper divisors (1).

721601059909 is an equidigital number, since it uses as much as digits as its factorization.

721601059909 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 306180, while the sum is 49.

The spelling of 721601059909 in words is "seven hundred twenty-one billion, six hundred one million, fifty-nine thousand, nine hundred nine".