671655623 has 2 divisors, whose sum is σ = 671655624. Its totient is φ = 671655622.

The previous prime is 671655619. The next prime is 671655653. The reversal of 671655623 is 326556176.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 671655623 - 2² = 671655619 is a prime.

It is a super-2 number, since 2×671655623² = 902242551815036258, which contains 22 as substring.

It is a Sophie Germain prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (671655653) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 335827811 + 335827812.

It is an arithmetic number, because the mean of its divisors is an integer number (335827812).

Almost surely, 2^671655623 is an apocalyptic number.

671655623 is a deficient number, since it is larger than the sum of its proper divisors (1).

671655623 is an equidigital number, since it uses as much as digits as its factorization.

671655623 is an evil number, because the sum of its binary digits is even.

The product of its digits is 226800, while the sum is 41.

The square root of 671655623 is about 25916.3196268297. The cubic root of 671655623 is about 875.7541788336.

The spelling of 671655623 in words is "six hundred seventy-one million, six hundred fifty-five thousand, six hundred twenty-three".