671123456 has 72 divisors (see below), whose sum is σ = 1380907710. Its totient is φ = 326025216.

The previous prime is 671123449. The next prime is 671123459. The reversal of 671123456 is 654321176.

It can be written as a sum of positive squares in only one way, i.e., 556205056 + 114918400 = 23584^2 + 10720^2 .

It is not an unprimeable number, because it can be changed into a prime (671123459) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 9193436 + ... + 9193508.

Almost surely, 2^671123456 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 671123456, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (690453855).

671123456 is an abundant number, since it is smaller than the sum of its proper divisors (709784254).

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

671123456 is an frugal number, since it uses more digits than its factorization.

671123456 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 229 (or 142 counting only the distinct ones).

The product of its digits is 30240, while the sum is 35.

The square root of 671123456 is about 25906.0505673868. The cubic root of 671123456 is about 875.5228248487.

The spelling of 671123456 in words is "six hundred seventy-one million, one hundred twenty-three thousand, four hundred fifty-six".