645485161 has 6 divisors (see below), whose sum is σ = 668511662. Its totient is φ = 623226240.

The previous prime is 645485129. The next prime is 645485171. The reversal of 645485161 is 161584546.

645485161 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 3 ways, for example, as 232379536 + 413105625 = 15244^2 + 20325^2 .

It is not a de Polignac number, because 645485161 - 2⁵ = 645485129 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (645485171) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 382920 + ... + 384601.

Almost surely, 2^645485161 is an apocalyptic number.

It is an amenable number.

645485161 is a deficient number, since it is larger than the sum of its proper divisors (23026501).

645485161 is an equidigital number, since it uses as much as digits as its factorization.

645485161 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 767579 (or 767550 counting only the distinct ones).

The product of its digits is 115200, while the sum is 40.

The square root of 645485161 is about 25406.4000007872. The cubic root of 645485161 is about 864.2288385794.

The spelling of 645485161 in words is "six hundred forty-five million, four hundred eighty-five thousand, one hundred sixty-one".