671923639 has 4 divisors (see below), whose sum is σ = 671975640. Its totient is φ = 671871640.

The previous prime is 671923631. The next prime is 671923687. The reversal of 671923639 is 936329176.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 671923639 - 2³ = 671923631 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 (671923631) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9972 + ... + 37990.

It is an arithmetic number, because the mean of its divisors is an integer number (167993910).

Almost surely, 2^671923639 is an apocalyptic number.

671923639 is a deficient number, since it is larger than the sum of its proper divisors (52001).

671923639 is a wasteful number, since it uses less digits than its factorization.

671923639 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 52000.

The product of its digits is 367416, while the sum is 46.

The square root of 671923639 is about 25921.4899070250. The cubic root of 671923639 is about 875.8706496910.

The spelling of 671923639 in words is "six hundred seventy-one million, nine hundred twenty-three thousand, six hundred thirty-nine".