671851 has 2 divisors, whose sum is σ = 671852. Its totient is φ = 671850.

The previous prime is 671837. The next prime is 671887. The reversal of 671851 is 158176.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 671851 - 2⁹ = 671339 is a prime.

It is not a weakly prime, because it can be changed into another prime (671831) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 335925 + 335926.

It is an arithmetic number, because the mean of its divisors is an integer number (335926).

2⁶⁷¹⁸⁵¹ is an apocalyptic number.

671851 is a deficient number, since it is larger than the sum of its proper divisors (1).

671851 is an equidigital number, since it uses as much as digits as its factorization.

671851 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1680, while the sum is 28.

The square root of 671851 is about 819.6651755443. The cubic root of 671851 is about 87.5839086253.

The spelling of 671851 in words is "six hundred seventy-one thousand, eight hundred fifty-one".