638742601 has 8 divisors (see below), whose sum is σ = 733181120. Its totient is φ = 545101488.

The previous prime is 638742553. The next prime is 638742623. The reversal of 638742601 is 106247836.

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

It is a cyclic number.

It is not a de Polignac number, because 638742601 - 2¹⁷ = 638611529 is a prime.

It is a super-2 number, since 2×638742601² = 815984220664490402, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (638742001) 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, 197631 + ... + 200836.

It is an arithmetic number, because the mean of its divisors is an integer number (91647640).

Almost surely, 2^638742601 is an apocalyptic number.

It is an amenable number.

638742601 is a deficient number, since it is larger than the sum of its proper divisors (94438519).

638742601 is a wasteful number, since it uses less digits than its factorization.

638742601 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 398703.

The product of its (nonzero) digits is 48384, while the sum is 37.

The square root of 638742601 is about 25273.3575331811. The cubic root of 638742601 is about 861.2091343326.

The spelling of 638742601 in words is "six hundred thirty-eight million, seven hundred forty-two thousand, six hundred one".