1671257191 has 2 divisors, whose sum is σ = 1671257192. Its totient is φ = 1671257190.

The previous prime is 1671257167. The next prime is 1671257209. The reversal of 1671257191 is 1917521761.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1671257191 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1671257101) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 835628595 + 835628596.

It is an arithmetic number, because the mean of its divisors is an integer number (835628596).

Almost surely, 2^1671257191 is an apocalyptic number.

1671257191 is a deficient number, since it is larger than the sum of its proper divisors (1).

1671257191 is an equidigital number, since it uses as much as digits as its factorization.

1671257191 is an evil number, because the sum of its binary digits is even.

The product of its digits is 26460, while the sum is 40.

The square root of 1671257191 is about 40881.0125975373. The cubic root of 1671257191 is about 1186.7186373194.

The spelling of 1671257191 in words is "one billion, six hundred seventy-one million, two hundred fifty-seven thousand, one hundred ninety-one".