671940612 has 72 divisors (see below), whose sum is σ = 1955431296. Its totient is φ = 190571904.

The previous prime is 671940611. The next prime is 671940649. The reversal of 671940612 is 216049176.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (671940611) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 24793 + ... + 44255.

It is an arithmetic number, because the mean of its divisors is an integer number (27158768).

Almost surely, 2^671940612 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 671940612, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (977715648).

671940612 is an abundant number, since it is smaller than the sum of its proper divisors (1283490684).

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

671940612 is a wasteful number, since it uses less digits than its factorization.

671940612 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19617 (or 19612 counting only the distinct ones).

The product of its (nonzero) digits is 18144, while the sum is 36.

The square root of 671940612 is about 25921.8172974041. The cubic root of 671940612 is about 875.8780245505.

Adding to 671940612 its reverse (216049176), we get a palindrome (887989788).

The spelling of 671940612 in words is "six hundred seventy-one million, nine hundred forty thousand, six hundred twelve".