671731648 has 56 divisors (see below), whose sum is σ = 1529173472. Its totient is φ = 286792704.

The previous prime is 671731637. The next prime is 671731649. The reversal of 671731648 is 846137176.

It is a tau number, because it is divible by the number of its divisors (56).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (671731649) 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, 121390 + ... + 126802.

Almost surely, 2^671731648 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 671731648, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (764586736).

671731648 is an abundant number, since it is smaller than the sum of its proper divisors (857441824).

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

671731648 is a wasteful number, since it uses less digits than its factorization.

671731648 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5709 (or 5699 counting only the distinct ones).

The product of its digits is 169344, while the sum is 43.

The square root of 671731648 is about 25917.7863252246. The cubic root of 671731648 is about 875.7872199226.

The spelling of 671731648 in words is "six hundred seventy-one million, seven hundred thirty-one thousand, six hundred forty-eight".