671502221 has 8 divisors (see below), whose sum is σ = 748093080. Its totient is φ = 598473792.

The previous prime is 671502203. The next prime is 671502257. The reversal of 671502221 is 122205176.

It can be written as a sum of positive squares in 4 ways, for example, as 134884996 + 536617225 = 11614^2 + 23165^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 671502221 - 2¹⁸ = 671240077 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (671502521) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 890210 + ... + 890963.

It is an arithmetic number, because the mean of its divisors is an integer number (93511635).

Almost surely, 2^671502221 is an apocalyptic number.

It is an amenable number.

671502221 is a deficient number, since it is larger than the sum of its proper divisors (76590859).

671502221 is a wasteful number, since it uses less digits than its factorization.

671502221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1781215.

The product of its (nonzero) digits is 1680, while the sum is 26.

The square root of 671502221 is about 25913.3598940778. The cubic root of 671502221 is about 875.6875014736.

Adding to 671502221 its reverse (122205176), we get a palindrome (793707397).

The spelling of 671502221 in words is "six hundred seventy-one million, five hundred two thousand, two hundred twenty-one".