253717323717421 has 2 divisors, whose sum is σ = 253717323717422. Its totient is φ = 253717323717420.

The previous prime is 253717323717343. The next prime is 253717323717443. The reversal of 253717323717421 is 124717323717352.

253717323717421 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 246961665020196 + 6755658697225 = 15715014^2 + 2599165^2 .

It is a cyclic number.

It is not a de Polignac number, because 253717323717421 - 2¹³ = 253717323709229 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (253717323517421) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 126858661858710 + 126858661858711.

It is an arithmetic number, because the mean of its divisors is an integer number (126858661858711).

Almost surely, 2^{253717323717421} is an apocalyptic number.

It is an amenable number.

253717323717421 is a deficient number, since it is larger than the sum of its proper divisors (1).

253717323717421 is an equidigital number, since it uses as much as digits as its factorization.

253717323717421 is an evil number, because the sum of its binary digits is even.

The product of its digits is 10372320, while the sum is 55.

The spelling of 253717323717421 in words is "two hundred fifty-three trillion, seven hundred seventeen billion, three hundred twenty-three million, seven hundred seventeen thousand, four hundred twenty-one".