663072423421 has 2 divisors, whose sum is σ = 663072423422. Its totient is φ = 663072423420.

The previous prime is 663072423401. The next prime is 663072423437. The reversal of 663072423421 is 124324270366.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 536043622500 + 127028800921 = 732150^2 + 356411^2 .

It is a cyclic number.

It is not a de Polignac number, because 663072423421 - 2⁵ = 663072423389 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (663072423401) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 331536211710 + 331536211711.

It is an arithmetic number, because the mean of its divisors is an integer number (331536211711).

Almost surely, 2^663072423421 is an apocalyptic number.

It is an amenable number.

663072423421 is a deficient number, since it is larger than the sum of its proper divisors (1).

663072423421 is an equidigital number, since it uses as much as digits as its factorization.

663072423421 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 290304, while the sum is 40.

Adding to 663072423421 its reverse (124324270366), we get a palindrome (787396693787).

The spelling of 663072423421 in words is "six hundred sixty-three billion, seventy-two million, four hundred twenty-three thousand, four hundred twenty-one".