671326621 has 16 divisors (see below), whose sum is σ = 793201024. Its totient is φ = 556222464.

The previous prime is 671326619. The next prime is 671326627. The reversal of 671326621 is 126623176.

It is a happy number.

It is not a de Polignac number, because 671326621 - 2¹ = 671326619 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (671326627) 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, 17701 + ... + 40693.

It is an arithmetic number, because the mean of its divisors is an integer number (49575064).

Almost surely, 2^671326621 is an apocalyptic number.

It is an amenable number.

671326621 is a deficient number, since it is larger than the sum of its proper divisors (121874403).

671326621 is a wasteful number, since it uses less digits than its factorization.

671326621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23140.

The product of its digits is 18144, while the sum is 34.

The square root of 671326621 is about 25909.9714588805. The cubic root of 671326621 is about 875.6111631154.

Adding to 671326621 its reverse (126623176), we get a palindrome (797949797).

The spelling of 671326621 in words is "six hundred seventy-one million, three hundred twenty-six thousand, six hundred twenty-one".