646171257 has 8 divisors (see below), whose sum is σ = 872467840. Its totient is φ = 425327760.

The previous prime is 646171217. The next prime is 646171259. The reversal of 646171257 is 752171646.

646171257 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 646171257 - 2¹⁶ = 646105721 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (646171259) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1362994 + ... + 1363467.

It is an arithmetic number, because the mean of its divisors is an integer number (109058480).

Almost surely, 2^646171257 is an apocalyptic number.

It is an amenable number.

646171257 is a deficient number, since it is larger than the sum of its proper divisors (226296583).

646171257 is a wasteful number, since it uses less digits than its factorization.

646171257 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2726543.

The product of its digits is 70560, while the sum is 39.

The square root of 646171257 is about 25419.8988392952. The cubic root of 646171257 is about 864.5349308161.

The spelling of 646171257 in words is "six hundred forty-six million, one hundred seventy-one thousand, two hundred fifty-seven".