6478857191 has 2 divisors, whose sum is σ = 6478857192. Its totient is φ = 6478857190.

The previous prime is 6478857173. The next prime is 6478857223. The reversal of 6478857191 is 1917588746.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 6478857191 - 2²⁶ = 6411748327 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6478857391) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3239428595 + 3239428596.

It is an arithmetic number, because the mean of its divisors is an integer number (3239428596).

Almost surely, 2^6478857191 is an apocalyptic number.

6478857191 is a deficient number, since it is larger than the sum of its proper divisors (1).

6478857191 is an equidigital number, since it uses as much as digits as its factorization.

6478857191 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3386880, while the sum is 56.

The square root of 6478857191 is about 80491.3485475302. The cubic root of 6478857191 is about 1864.2298991883.

The spelling of 6478857191 in words is "six billion, four hundred seventy-eight million, eight hundred fifty-seven thousand, one hundred ninety-one".