671568520 has 192 divisors, whose sum is σ = 1843475760. Its totient is φ = 219340800.

The previous prime is 671568497. The next prime is 671568523. The reversal of 671568520 is 25865176.

It can be written as a sum of positive squares in 8 ways, for example, as 20196036 + 651372484 = 4494^2 + 25522^2 .

It is a Harshad number since it is a multiple of its sum of digits (40).

It is not an unprimeable number, because it can be changed into a prime (671568523) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 4901892 + ... + 4902028.

Almost surely, 2^671568520 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 671568520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (921737880).

671568520 is an abundant number, since it is smaller than the sum of its proper divisors (1171907240).

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

671568520 is a wasteful number, since it uses less digits than its factorization.

671568520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 264 (or 253 counting only the distinct ones).

The product of its (nonzero) digits is 100800, while the sum is 40.

The square root of 671568520 is about 25914.6391061114. The cubic root of 671568520 is about 875.7163200901.

The spelling of 671568520 in words is "six hundred seventy-one million, five hundred sixty-eight thousand, five hundred twenty".