671808871 has 2 divisors, whose sum is σ = 671808872. Its totient is φ = 671808870.

The previous prime is 671808847. The next prime is 671808877. The reversal of 671808871 is 178808176.

671808871 = 10579² + 10580² + ... + 10584².

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 671808871 - 2⁷ = 671808743 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (671808877) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 335904435 + 335904436.

It is an arithmetic number, because the mean of its divisors is an integer number (335904436).

Almost surely, 2^671808871 is an apocalyptic number.

671808871 is a deficient number, since it is larger than the sum of its proper divisors (1).

671808871 is an equidigital number, since it uses as much as digits as its factorization.

671808871 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 150528, while the sum is 46.

The square root of 671808871 is about 25919.2760508468. The cubic root of 671808871 is about 875.8207791200.

The spelling of 671808871 in words is "six hundred seventy-one million, eight hundred eight thousand, eight hundred seventy-one".