671887638 has 24 divisors (see below), whose sum is σ = 1519051248. Its totient is φ = 214224912.

The previous prime is 671887621. The next prime is 671887649. The reversal of 671887638 is 836788176.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 811045 + ... + 811872.

It is an arithmetic number, because the mean of its divisors is an integer number (63293802).

Almost surely, 2^671887638 is an apocalyptic number.

671887638 is an abundant number, since it is smaller than the sum of its proper divisors (847163610).

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

671887638 is a wasteful number, since it uses less digits than its factorization.

671887638 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1622948 (or 1622945 counting only the distinct ones).

The product of its digits is 2709504, while the sum is 54.

The square root of 671887638 is about 25920.7954739047. The cubic root of 671887638 is about 875.8550066523.

The spelling of 671887638 in words is "six hundred seventy-one million, eight hundred eighty-seven thousand, six hundred thirty-eight".