261360644 has 24 divisors (see below), whose sum is σ = 475167000. Its totient is φ = 125637120.

The previous prime is 261360643. The next prime is 261360667. The reversal of 261360644 is 446063162.

It can be written as a sum of positive squares in 4 ways, for example, as 119464900 + 141895744 = 10930^2 + 11912^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 261360644.

It is not an unprimeable number, because it can be changed into a prime (261360641) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 23282 + ... + 32630.

It is an arithmetic number, because the mean of its divisors is an integer number (19798625).

Almost surely, 2^261360644 is an apocalyptic number.

It is an amenable number.

261360644 is a deficient number, since it is larger than the sum of its proper divisors (213806356).

261360644 is a wasteful number, since it uses less digits than its factorization.

261360644 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9623 (or 9621 counting only the distinct ones).

The product of its (nonzero) digits is 20736, while the sum is 32.

The square root of 261360644 is about 16166.6522199248. The cubic root of 261360644 is about 639.3618671956.

The spelling of 261360644 in words is "two hundred sixty-one million, three hundred sixty thousand, six hundred forty-four".