671979138 has 8 divisors (see below), whose sum is σ = 1343958288. Its totient is φ = 223993044.

The previous prime is 671979131. The next prime is 671979149. The reversal of 671979138 is 831979176.

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

671979138 is an admirable number.

It is not an unprimeable number, because it can be changed into a prime (671979131) 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 3 ways as a sum of consecutive naturals, for example, 55998256 + ... + 55998267.

It is an arithmetic number, because the mean of its divisors is an integer number (167994786).

Almost surely, 2^671979138 is an apocalyptic number.

671979138 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

671979138 is a wasteful number, since it uses less digits than its factorization.

671979138 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 111996528.

The product of its digits is 571536, while the sum is 51.

The square root of 671979138 is about 25922.5604059476. The cubic root of 671979138 is about 875.8947638433.

The spelling of 671979138 in words is "six hundred seventy-one million, nine hundred seventy-nine thousand, one hundred thirty-eight".