671651 has 2 divisors, whose sum is σ = 671652. Its totient is φ = 671650.

The previous prime is 671647. The next prime is 671681. The reversal of 671651 is 156176.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 671651 - 2² = 671647 is a prime.

It is a super-2 number, since 2×671651² = 902230131602, which contains 22 as substring.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 671651.

It is not a weakly prime, because it can be changed into another prime (671681) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 335825 + 335826.

It is an arithmetic number, because the mean of its divisors is an integer number (335826).

2⁶⁷¹⁶⁵¹ is an apocalyptic number.

671651 is a deficient number, since it is larger than the sum of its proper divisors (1).

671651 is an equidigital number, since it uses as much as digits as its factorization.

671651 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1260, while the sum is 26.

The square root of 671651 is about 819.5431654282. The cubic root of 671651 is about 87.5752169559.

The spelling of 671651 in words is "six hundred seventy-one thousand, six hundred fifty-one".