671380621 has 2 divisors, whose sum is σ = 671380622. Its totient is φ = 671380620.

The previous prime is 671380613. The next prime is 671380639. The reversal of 671380621 is 126083176.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 614544100 + 56836521 = 24790^2 + 7539^2 .

It is a cyclic number.

It is not a de Polignac number, because 671380621 - 2³ = 671380613 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (671380321) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 335690310 + 335690311.

It is an arithmetic number, because the mean of its divisors is an integer number (335690311).

Almost surely, 2^671380621 is an apocalyptic number.

It is an amenable number.

671380621 is a deficient number, since it is larger than the sum of its proper divisors (1).

671380621 is an equidigital number, since it uses as much as digits as its factorization.

671380621 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 12096, while the sum is 34.

The square root of 671380621 is about 25911.0135077731. The cubic root of 671380621 is about 875.6346398820.

The spelling of 671380621 in words is "six hundred seventy-one million, three hundred eighty thousand, six hundred twenty-one".