6439957525 has 12 divisors (see below), whose sum is σ = 7988793124. Its totient is φ = 5149872000.

The previous prime is 6439957507. The next prime is 6439957541. The reversal of 6439957525 is 5257599346.

It can be written as a sum of positive squares in 6 ways, for example, as 3600240004 + 2839717521 = 60002^2 + 53289^2 .

It is not a de Polignac number, because 6439957525 - 2²³ = 6431568917 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 11935 + ... + 114115.

Almost surely, 2^6439957525 is an apocalyptic number.

It is an amenable number.

6439957525 is a deficient number, since it is larger than the sum of its proper divisors (1548835599).

6439957525 is a wasteful number, since it uses less digits than its factorization.

6439957525 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 104712 (or 104707 counting only the distinct ones).

The product of its digits is 10206000, while the sum is 55.

The square root of 6439957525 is about 80249.3459474904. The cubic root of 6439957525 is about 1860.4914033836.

The spelling of 6439957525 in words is "six billion, four hundred thirty-nine million, nine hundred fifty-seven thousand, five hundred twenty-five".