671480021 has 2 divisors, whose sum is σ = 671480022. Its totient is φ = 671480020.

The previous prime is 671480011. The next prime is 671480027. The reversal of 671480021 is 120084176.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 567154225 + 104325796 = 23815^2 + 10214^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-671480021 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (671480027) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 335740010 + 335740011.

It is an arithmetic number, because the mean of its divisors is an integer number (335740011).

Almost surely, 2^671480021 is an apocalyptic number.

It is an amenable number.

671480021 is a deficient number, since it is larger than the sum of its proper divisors (1).

671480021 is an equidigital number, since it uses as much as digits as its factorization.

671480021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2688, while the sum is 29.

The square root of 671480021 is about 25912.9315400632. The cubic root of 671480021 is about 875.6778512316.

The spelling of 671480021 in words is "six hundred seventy-one million, four hundred eighty thousand, twenty-one".