671521571 has 16 divisors (see below), whose sum is σ = 784988160. Its totient is φ = 562476960.

The previous prime is 671521561. The next prime is 671521577. The reversal of 671521571 is 175125176.

It is a cyclic number.

It is not a de Polignac number, because 671521571 - 2⁶ = 671521507 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (671521577) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 301241 + ... + 303461.

It is an arithmetic number, because the mean of its divisors is an integer number (49061760).

Almost surely, 2^671521571 is an apocalyptic number.

671521571 is a deficient number, since it is larger than the sum of its proper divisors (113466589).

671521571 is a wasteful number, since it uses less digits than its factorization.

671521571 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3194.

The product of its digits is 14700, while the sum is 35.

The square root of 671521571 is about 25913.7332509231. The cubic root of 671521571 is about 875.6959126596.

The spelling of 671521571 in words is "six hundred seventy-one million, five hundred twenty-one thousand, five hundred seventy-one".