635998275025 has 9 divisors (see below), whose sum is σ = 788642805531. Its totient is φ = 508795430040.

The previous prime is 635998275023. The next prime is 635998275041. The reversal of 635998275025 is 520572899536.

The square root of 635998275025 is 797495.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 228959379009 + 407038896016 = 478497^2 + 637996^2 .

It is not a de Polignac number, because 635998275025 - 2¹ = 635998275023 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (635998275023) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 3907726 + ... + 4067224.

Almost surely, 2^635998275025 is an apocalyptic number.

635998275025 is the 797495-th square number.

635998275025 is the 398748-th centered octagonal number.

It is an amenable number.

635998275025 is a deficient number, since it is larger than the sum of its proper divisors (152644530506).

635998275025 is an frugal number, since it uses more digits than its factorization.

635998275025 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 319008 (or 159504 counting only the distinct ones).

The product of its (nonzero) digits is 40824000, while the sum is 61.

The spelling of 635998275025 in words is "six hundred thirty-five billion, nine hundred ninety-eight million, two hundred seventy-five thousand, twenty-five".