638532277469 has 2 divisors, whose sum is σ = 638532277470. Its totient is φ = 638532277468.

The previous prime is 638532277441. The next prime is 638532277483. The reversal of 638532277469 is 964772235836.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 536793606244 + 101738671225 = 732662^2 + 318965^2 .

It is a cyclic number.

It is not a de Polignac number, because 638532277469 - 2²⁰ = 638531228893 is a prime.

It is a super-2 number, since 2×638532277469² (a number of 24 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (638532271469) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 319266138734 + 319266138735.

It is an arithmetic number, because the mean of its divisors is an integer number (319266138735).

Almost surely, 2^638532277469 is an apocalyptic number.

It is an amenable number.

638532277469 is a deficient number, since it is larger than the sum of its proper divisors (1).

638532277469 is an equidigital number, since it uses as much as digits as its factorization.

638532277469 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 91445760, while the sum is 62.

The spelling of 638532277469 in words is "six hundred thirty-eight billion, five hundred thirty-two million, two hundred seventy-seven thousand, four hundred sixty-nine".