671721732 has 72 divisors (see below), whose sum is σ = 1858514112. Its totient is φ = 202872000.

The previous prime is 671721727. The next prime is 671721761. The reversal of 671721732 is 237127176.

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

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 122857 + ... + 128207.

It is an arithmetic number, because the mean of its divisors is an integer number (25812696).

Almost surely, 2^671721732 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 671721732, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (929257056).

671721732 is an abundant number, since it is smaller than the sum of its proper divisors (1186792380).

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

671721732 is a wasteful number, since it uses less digits than its factorization.

671721732 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5689 (or 5684 counting only the distinct ones).

The product of its digits is 24696, while the sum is 36.

The square root of 671721732 is about 25917.5950273169. The cubic root of 671721732 is about 875.7829104890.

The spelling of 671721732 in words is "six hundred seventy-one million, seven hundred twenty-one thousand, seven hundred thirty-two".