642635554525 has 6 divisors (see below), whose sum is σ = 796868087642. Its totient is φ = 514108443600.

The previous prime is 642635554489. The next prime is 642635554559. The reversal of 642635554525 is 525455536246.

It can be written as a sum of positive squares in 3 ways, for example, as 911194596 + 641724359929 = 30186^2 + 801077^2 .

It is not a de Polignac number, because 642635554525 - 2⁷ = 642635554397 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 5 ways as a sum of consecutive naturals, for example, 12852711066 + ... + 12852711115.

Almost surely, 2^642635554525 is an apocalyptic number.

It is an amenable number.

642635554525 is a deficient number, since it is larger than the sum of its proper divisors (154232533117).

642635554525 is a wasteful number, since it uses less digits than its factorization.

642635554525 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25705422191 (or 25705422186 counting only the distinct ones).

The product of its digits is 21600000, while the sum is 52.

The spelling of 642635554525 in words is "six hundred forty-two billion, six hundred thirty-five million, five hundred fifty-four thousand, five hundred twenty-five".