643435576757725 has 6 divisors (see below), whose sum is σ = 797860115179610. Its totient is φ = 514748461406160.

The previous prime is 643435576757683. The next prime is 643435576757741. The reversal of 643435576757725 is 527757675534346.

It can be written as a sum of positive squares in 3 ways, for example, as 156141151609 + 643279435606116 = 395147^2 + 25362954^2 .

It is not a de Polignac number, because 643435576757725 - 2¹⁷ = 643435576626653 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 12868711535130 + ... + 12868711535179.

Almost surely, 2^{643435576757725} is an apocalyptic number.

It is an amenable number.

643435576757725 is a deficient number, since it is larger than the sum of its proper divisors (154424538421885).

643435576757725 is a wasteful number, since it uses less digits than its factorization.

643435576757725 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25737423070319 (or 25737423070314 counting only the distinct ones).

The product of its digits is 15558480000, while the sum is 76.

The spelling of 643435576757725 in words is "six hundred forty-three trillion, four hundred thirty-five billion, five hundred seventy-six million, seven hundred fifty-seven thousand, seven hundred twenty-five".