638101639 has 8 divisors (see below), whose sum is σ = 746218880. Its totient is φ = 534224376.

The previous prime is 638101619. The next prime is 638101679. The reversal of 638101639 is 936101836.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 638101639 - 2⁹ = 638101127 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 638101598 and 638101607.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (638101619) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1059669 + ... + 1060270.

It is an arithmetic number, because the mean of its divisors is an integer number (93277360).

Almost surely, 2^638101639 is an apocalyptic number.

638101639 is a deficient number, since it is larger than the sum of its proper divisors (108117241).

638101639 is a wasteful number, since it uses less digits than its factorization.

638101639 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2119989.

The product of its (nonzero) digits is 23328, while the sum is 37.

The square root of 638101639 is about 25260.6737637776. The cubic root of 638101639 is about 860.9209707482.

The spelling of 638101639 in words is "six hundred thirty-eight million, one hundred one thousand, six hundred thirty-nine".