3639961305 has 12 divisors (see below), whose sum is σ = 6309266340. Its totient is φ = 1941312672.

The previous prime is 3639961289. The next prime is 3639961363. The reversal of 3639961305 is 5031699363.

3639961305 is a `hidden beast` number, since 3 + 639 + 9 + 6 + 1 + 3 + 0 + 5 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 1482173001 + 2157788304 = 38499^2 + 46452^2 .

It is not a de Polignac number, because 3639961305 - 2⁴ = 3639961289 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45), and also a Moran number because the ratio is a prime number: 80888029 = 3639961305 / (3 + 6 + 3 + 9 + 9 + 6 + 1 + 3 + 0 + 5).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 40443970 + ... + 40444059.

It is an arithmetic number, because the mean of its divisors is an integer number (525772195).

Almost surely, 2^3639961305 is an apocalyptic number.

It is an amenable number.

3639961305 is a deficient number, since it is larger than the sum of its proper divisors (2669305035).

3639961305 is a wasteful number, since it uses less digits than its factorization.

3639961305 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 80888040 (or 80888037 counting only the distinct ones).

The product of its (nonzero) digits is 393660, while the sum is 45.

The square root of 3639961305 is about 60332.0918334513. The cubic root of 3639961305 is about 1538.2688853046.

The spelling of 3639961305 in words is "three billion, six hundred thirty-nine million, nine hundred sixty-one thousand, three hundred five".