638375013643 has 2 divisors, whose sum is σ = 638375013644. Its totient is φ = 638375013642.

The previous prime is 638375013611. The next prime is 638375013659. The reversal of 638375013643 is 346310573836.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 638375013643 - 2⁵ = 638375013611 is a prime.

It is a super-2 number, since 2×638375013643² (a number of 24 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (638375011643) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 319187506821 + 319187506822.

It is an arithmetic number, because the mean of its divisors is an integer number (319187506822).

Almost surely, 2^638375013643 is an apocalyptic number.

638375013643 is a deficient number, since it is larger than the sum of its proper divisors (1).

638375013643 is an equidigital number, since it uses as much as digits as its factorization.

638375013643 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3265920, while the sum is 49.

The spelling of 638375013643 in words is "six hundred thirty-eight billion, three hundred seventy-five million, thirteen thousand, six hundred forty-three".