261444164 has 24 divisors (see below), whose sum is σ = 474427800. Its totient is φ = 125914880.

The previous prime is 261444149. The next prime is 261444181. The reversal of 261444164 is 461444162.

It can be written as a sum of positive squares in 4 ways, for example, as 42640900 + 218803264 = 6530^2 + 14792^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 261444164.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 51032 + ... + 55920.

It is an arithmetic number, because the mean of its divisors is an integer number (19767825).

Almost surely, 2^261444164 is an apocalyptic number.

It is an amenable number.

261444164 is a deficient number, since it is larger than the sum of its proper divisors (212983636).

261444164 is a wasteful number, since it uses less digits than its factorization.

261444164 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5383 (or 5381 counting only the distinct ones).

The product of its digits is 18432, while the sum is 32.

The square root of 261444164 is about 16169.2351086871. The cubic root of 261444164 is about 639.4299644363.

The spelling of 261444164 in words is "two hundred sixty-one million, four hundred forty-four thousand, one hundred sixty-four".