1643052205 has 16 divisors (see below), whose sum is σ = 2026678320. Its totient is φ = 1278204928.

The previous prime is 1643052197. The next prime is 1643052221. The reversal of 1643052205 is 5022503461.

It can be written as a sum of positive squares in 8 ways, for example, as 398162116 + 1244890089 = 19954^2 + 35283^2 .

It is a cyclic number.

It is not a de Polignac number, because 1643052205 - 2³ = 1643052197 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2511 + ... + 57379.

It is an arithmetic number, because the mean of its divisors is an integer number (126667395).

Almost surely, 2^1643052205 is an apocalyptic number.

It is an amenable number.

1643052205 is a deficient number, since it is larger than the sum of its proper divisors (383626115).

1643052205 is a wasteful number, since it uses less digits than its factorization.

1643052205 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 55040.

The product of its (nonzero) digits is 7200, while the sum is 28.

The square root of 1643052205 is about 40534.5803604774. The cubic root of 1643052205 is about 1180.0048369523.

Adding to 1643052205 its reverse (5022503461), we get a palindrome (6665555666).

It can be divided in two parts, 16430 and 52205, that added together give a triangular number (68635 = T₃₇₀).

The spelling of 1643052205 in words is "one billion, six hundred forty-three million, fifty-two thousand, two hundred five".