671447261 has 2 divisors, whose sum is σ = 671447262. Its totient is φ = 671447260.

The previous prime is 671447219. The next prime is 671447281. The reversal of 671447261 is 162744176.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 492396100 + 179051161 = 22190^2 + 13381^2 .

It is a cyclic number.

It is not a de Polignac number, because 671447261 - 2¹⁸ = 671185117 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (671447281) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 335723630 + 335723631.

It is an arithmetic number, because the mean of its divisors is an integer number (335723631).

Almost surely, 2^671447261 is an apocalyptic number.

It is an amenable number.

671447261 is a deficient number, since it is larger than the sum of its proper divisors (1).

671447261 is an equidigital number, since it uses as much as digits as its factorization.

671447261 is an evil number, because the sum of its binary digits is even.

The product of its digits is 56448, while the sum is 38.

The square root of 671447261 is about 25912.2994155285. The cubic root of 671447261 is about 875.6636102157.

The spelling of 671447261 in words is "six hundred seventy-one million, four hundred forty-seven thousand, two hundred sixty-one".