42723441721 has 2 divisors, whose sum is σ = 42723441722. Its totient is φ = 42723441720.

The previous prime is 42723441701. The next prime is 42723441737. The reversal of 42723441721 is 12714432724.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 30366896121 + 12356545600 = 174261^2 + 111160^2 .

It is a cyclic number.

It is not a de Polignac number, because 42723441721 - 2¹⁵ = 42723408953 is a prime.

It is not a weakly prime, because it can be changed into another prime (42723441701) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21361720860 + 21361720861.

It is an arithmetic number, because the mean of its divisors is an integer number (21361720861).

Almost surely, 2^42723441721 is an apocalyptic number.

It is an amenable number.

42723441721 is a deficient number, since it is larger than the sum of its proper divisors (1).

42723441721 is an equidigital number, since it uses as much as digits as its factorization.

42723441721 is an evil number, because the sum of its binary digits is even.

The product of its digits is 75264, while the sum is 37.

The spelling of 42723441721 in words is "forty-two billion, seven hundred twenty-three million, four hundred forty-one thousand, seven hundred twenty-one".