1643143625 has 32 divisors (see below), whose sum is σ = 2143683360. Its totient is φ = 1255833600.

The previous prime is 1643143609. The next prime is 1643143643. The reversal of 1643143625 is 5263413461.

It can be written as a sum of positive squares in 16 ways, for example, as 716793529 + 926350096 = 26773^2 + 30436^2 .

It is not a de Polignac number, because 1643143625 - 2⁴ = 1643143609 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 349289 + ... + 353961.

It is an arithmetic number, because the mean of its divisors is an integer number (66990105).

Almost surely, 2^1643143625 is an apocalyptic number.

It is an amenable number.

1643143625 is a deficient number, since it is larger than the sum of its proper divisors (500539735).

1643143625 is an equidigital number, since it uses as much as digits as its factorization.

1643143625 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4814 (or 4804 counting only the distinct ones).

The product of its digits is 51840, while the sum is 35.

The square root of 1643143625 is about 40535.7080239139. The cubic root of 1643143625 is about 1180.0267218405.

The spelling of 1643143625 in words is "one billion, six hundred forty-three million, one hundred forty-three thousand, six hundred twenty-five".