643116625 has 8 divisors (see below), whose sum is σ = 802609704. Its totient is φ = 514493200.

The previous prime is 643116623. The next prime is 643116659. The reversal of 643116625 is 526611346.

It can be written as a sum of positive squares in 4 ways, for example, as 66732561 + 576384064 = 8169^2 + 24008^2 .

It is not a de Polignac number, because 643116625 - 2¹ = 643116623 is a prime.

It is a super-3 number, since 3×643116625³ (a number of 27 digits) contains 333 as substring.

It is a hoax number, since the sum of its digits (34) coincides with the sum of the digits of its distinct prime factors.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (643116623) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2572342 + ... + 2572591.

It is an arithmetic number, because the mean of its divisors is an integer number (100326213).

Almost surely, 2^643116625 is an apocalyptic number.

It is an amenable number.

643116625 is a deficient number, since it is larger than the sum of its proper divisors (159493079).

643116625 is an equidigital number, since it uses as much as digits as its factorization.

643116625 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5144948 (or 5144938 counting only the distinct ones).

The product of its digits is 25920, while the sum is 34.

The square root of 643116625 is about 25359.7441824637. The cubic root of 643116625 is about 863.1704791466.

The spelling of 643116625 in words is "six hundred forty-three million, one hundred sixteen thousand, six hundred twenty-five".