638414478 has 48 divisors (see below), whose sum is σ = 1568046480. Its totient is φ = 186095232.

The previous prime is 638414431. The next prime is 638414479. The reversal of 638414478 is 874414836.

638414478 is a `hidden beast` number, since 638 + 4 + 1 + 4 + 4 + 7 + 8 = 666.

638414478 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (638414479) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 67351 + ... + 76242.

It is an arithmetic number, because the mean of its divisors is an integer number (32667635).

Almost surely, 2^638414478 is an apocalyptic number.

638414478 is an abundant number, since it is smaller than the sum of its proper divisors (929632002).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

638414478 is a wasteful number, since it uses less digits than its factorization.

638414478 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 143633 (or 143630 counting only the distinct ones).

The product of its digits is 516096, while the sum is 45.

The square root of 638414478 is about 25266.8652190967. The cubic root of 638414478 is about 861.0616409470.

The spelling of 638414478 in words is "six hundred thirty-eight million, four hundred fourteen thousand, four hundred seventy-eight".