638144901 has 12 divisors (see below), whose sum is σ = 929024512. Its totient is φ = 422079336.

The previous prime is 638144891. The next prime is 638144987. The reversal of 638144901 is 109441836.

638144901 is a `hidden beast` number, since 638 + 14 + 4 + 9 + 0 + 1 = 666.

It is not a de Polignac number, because 638144901 - 2¹⁵ = 638112133 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (638144201) 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 11 ways as a sum of consecutive naturals, for example, 278011 + ... + 280296.

Almost surely, 2^638144901 is an apocalyptic number.

It is an amenable number.

638144901 is a deficient number, since it is larger than the sum of its proper divisors (290879611).

638144901 is a wasteful number, since it uses less digits than its factorization.

638144901 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 558440 (or 558437 counting only the distinct ones).

The product of its (nonzero) digits is 20736, while the sum is 36.

The square root of 638144901 is about 25261.5300605486. The cubic root of 638144901 is about 860.9404265418.

The spelling of 638144901 in words is "six hundred thirty-eight million, one hundred forty-four thousand, nine hundred one".