642706605269 has 2 divisors, whose sum is σ = 642706605270. Its totient is φ = 642706605268.

The previous prime is 642706605239. The next prime is 642706605293. The reversal of 642706605269 is 962506607246.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 642342940369 + 363664900 = 801463^2 + 19070^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-642706605269 is a prime.

It is a super-2 number, since 2×642706605269² (a number of 24 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 642706605269.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (642706605239) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 321353302634 + 321353302635.

It is an arithmetic number, because the mean of its divisors is an integer number (321353302635).

Almost surely, 2^642706605269 is an apocalyptic number.

It is an amenable number.

642706605269 is a deficient number, since it is larger than the sum of its proper divisors (1).

642706605269 is an equidigital number, since it uses as much as digits as its factorization.

642706605269 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 6531840, while the sum is 53.

The spelling of 642706605269 in words is "six hundred forty-two billion, seven hundred six million, six hundred five thousand, two hundred sixty-nine".