671663560 has 32 divisors (see below), whose sum is σ = 1512156600. Its totient is φ = 268503040.

The previous prime is 671663539. The next prime is 671663563. The reversal of 671663560 is 65366176.

It can be written as a sum of positive squares in 4 ways, for example, as 263542756 + 408120804 = 16234^2 + 20202^2 .

It is a super-2 number, since 2×671663560² = 902263875663747200, which contains 22 as substring.

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 (671663563) 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, 79206 + ... + 87274.

Almost surely, 2^671663560 is an apocalyptic number.

It is an amenable number.

671663560 is an abundant number, since it is smaller than the sum of its proper divisors (840493040).

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

671663560 is a wasteful number, since it uses less digits than its factorization.

671663560 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10161 (or 10157 counting only the distinct ones).

The product of its (nonzero) digits is 136080, while the sum is 40.

The square root of 671663560 is about 25916.4727538298. The cubic root of 671663560 is about 875.7576284355.

The spelling of 671663560 in words is "six hundred seventy-one million, six hundred sixty-three thousand, five hundred sixty".