2644561161 has 24 divisors (see below), whose sum is σ = 4205435520. Its totient is φ = 1588053600.

The previous prime is 2644561147. The next prime is 2644561163. The reversal of 2644561161 is 1611654462.

2644561161 is a `hidden beast` number, since 2 + 644 + 5 + 6 + 1 + 1 + 6 + 1 = 666.

It is not a de Polignac number, because 2644561161 - 2⁹ = 2644560649 is a prime.

It is not an unprimeable number, because it can be changed into a prime (2644561163) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 111745 + ... + 133326.

It is an arithmetic number, because the mean of its divisors is an integer number (175226480).

Almost surely, 2^2644561161 is an apocalyptic number.

It is an amenable number.

2644561161 is a deficient number, since it is larger than the sum of its proper divisors (1560874359).

2644561161 is a wasteful number, since it uses less digits than its factorization.

2644561161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 245197 (or 245194 counting only the distinct ones).

The product of its digits is 34560, while the sum is 36.

The square root of 2644561161 is about 51425.2968975387. The cubic root of 2644561161 is about 1382.8801363581.

The spelling of 2644561161 in words is "two billion, six hundred forty-four million, five hundred sixty-one thousand, one hundred sixty-one".