671879640 has 32 divisors (see below), whose sum is σ = 2015639280. Its totient is φ = 179167872.

The previous prime is 671879623. The next prime is 671879641. The reversal of 671879640 is 46978176.

It is a self number, because there is not a number n which added to its sum of digits gives 671879640.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (671879641) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2799379 + ... + 2799618.

Almost surely, 2^671879640 is an apocalyptic number.

671879640 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

671879640 is an abundant number, since it is smaller than the sum of its proper divisors (1343759640).

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

671879640 is a wasteful number, since it uses less digits than its factorization.

671879640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5599011 (or 5599007 counting only the distinct ones).

The product of its (nonzero) digits is 508032, while the sum is 48.

The square root of 671879640 is about 25920.6411957729. The cubic root of 671879640 is about 875.8515313112.

The spelling of 671879640 in words is "six hundred seventy-one million, eight hundred seventy-nine thousand, six hundred forty".