671638992 has 80 divisors (see below), whose sum is σ = 1851881472. Its totient is φ = 209018880.

The previous prime is 671638987. The next prime is 671639011. The reversal of 671638992 is 299836176.

It is a Harshad number since it is a multiple of its sum of digits (51).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 100392 + ... + 106872.

Almost surely, 2^671638992 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 671638992, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (925940736).

671638992 is an abundant number, since it is smaller than the sum of its proper divisors (1180242480).

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

671638992 is a wasteful number, since it uses less digits than its factorization.

671638992 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6636 (or 6630 counting only the distinct ones).

The product of its digits is 979776, while the sum is 51.

The square root of 671638992 is about 25915.9987652415. The cubic root of 671638992 is about 875.7469505322.

The spelling of 671638992 in words is "six hundred seventy-one million, six hundred thirty-eight thousand, nine hundred ninety-two".