671656520 has 16 divisors (see below), whose sum is σ = 1511227260. Its totient is φ = 268662592.

The previous prime is 671656483. The next prime is 671656537. The reversal of 671656520 is 25656176.

It can be written as a sum of positive squares in 2 ways, for example, as 666982276 + 4674244 = 25826^2 + 2162^2 .

It is a super-2 number, since 2×671656520² = 902244961717020800, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8395667 + ... + 8395746.

Almost surely, 2^671656520 is an apocalyptic number.

It is an amenable number.

671656520 is an abundant number, since it is smaller than the sum of its proper divisors (839570740).

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

671656520 is a wasteful number, since it uses less digits than its factorization.

671656520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16791424 (or 16791420 counting only the distinct ones).

The product of its (nonzero) digits is 75600, while the sum is 38.

The square root of 671656520 is about 25916.3369325219. The cubic root of 671656520 is about 875.7545686917.

It can be divided in two parts, 6716 and 56520, that added together give a palindrome (63236).

The spelling of 671656520 in words is "six hundred seventy-one million, six hundred fifty-six thousand, five hundred twenty".