6438085657 has 18 divisors (see below), whose sum is σ = 6894604158. Its totient is φ = 6010564608.

The previous prime is 6438085631. The next prime is 6438085711. The reversal of 6438085657 is 7565808346.

It can be written as a sum of positive squares in 3 ways, for example, as 3589088281 + 2848997376 = 59909^2 + 53376^2 .

It is not a de Polignac number, because 6438085657 - 2¹¹ = 6438083609 is a prime.

It is a Smith number, since the sum of its digits (52) coincides with the sum of the digits of its prime factors.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (6438085627) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 5583193 + ... + 5584345.

Almost surely, 2^6438085657 is an apocalyptic number.

It is an amenable number.

6438085657 is a deficient number, since it is larger than the sum of its proper divisors (456518501).

6438085657 is a wasteful number, since it uses less digits than its factorization.

6438085657 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1465 (or 1309 counting only the distinct ones).

The product of its (nonzero) digits is 4838400, while the sum is 52.

The square root of 6438085657 is about 80237.6822758484. The cubic root of 6438085657 is about 1860.3111262216.

The spelling of 6438085657 in words is "six billion, four hundred thirty-eight million, eighty-five thousand, six hundred fifty-seven".