638405471375 has 64 divisors (see below), whose sum is σ = 951269529600. Its totient is φ = 418231756800.

The previous prime is 638405471369. The next prime is 638405471383. The reversal of 638405471375 is 573174504836.

It is not a de Polignac number, because 638405471375 - 2¹⁴ = 638405454991 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 17268911 + ... + 17305839.

It is an arithmetic number, because the mean of its divisors is an integer number (14863586400).

Almost surely, 2^638405471375 is an apocalyptic number.

638405471375 is a deficient number, since it is larger than the sum of its proper divisors (312864058225).

638405471375 is a wasteful number, since it uses less digits than its factorization.

638405471375 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 37833 (or 37823 counting only the distinct ones).

The product of its (nonzero) digits is 8467200, while the sum is 53.

The spelling of 638405471375 in words is "six hundred thirty-eight billion, four hundred five million, four hundred seventy-one thousand, three hundred seventy-five".