671974421 has 2 divisors, whose sum is σ = 671974422. Its totient is φ = 671974420.

The previous prime is 671974409. The next prime is 671974447. The reversal of 671974421 is 124479176.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 528310225 + 143664196 = 22985^2 + 11986^2 .

It is a cyclic number.

It is not a de Polignac number, because 671974421 - 2¹⁰ = 671973397 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (611974421) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 335987210 + 335987211.

It is an arithmetic number, because the mean of its divisors is an integer number (335987211).

Almost surely, 2^671974421 is an apocalyptic number.

It is an amenable number.

671974421 is a deficient number, since it is larger than the sum of its proper divisors (1).

671974421 is an equidigital number, since it uses as much as digits as its factorization.

671974421 is an evil number, because the sum of its binary digits is even.

The product of its digits is 84672, while the sum is 41.

The square root of 671974421 is about 25922.4694232629. The cubic root of 671974421 is about 875.8927143723.

The spelling of 671974421 in words is "six hundred seventy-one million, nine hundred seventy-four thousand, four hundred twenty-one".