261766945 has 16 divisors (see below), whose sum is σ = 353733120. Its totient is φ = 184233600.

The previous prime is 261766907. The next prime is 261766949. The reversal of 261766945 is 549667162.

It is not a de Polignac number, because 261766945 - 2¹¹ = 261764897 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 261766895 and 261766904.

It is not an unprimeable number, because it can be changed into a prime (261766949) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 75060 + ... + 78469.

It is an arithmetic number, because the mean of its divisors is an integer number (22108320).

Almost surely, 2^261766945 is an apocalyptic number.

It is an amenable number.

261766945 is a deficient number, since it is larger than the sum of its proper divisors (91966175).

261766945 is a wasteful number, since it uses less digits than its factorization.

261766945 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 153576.

The product of its digits is 544320, while the sum is 46.

The square root of 261766945 is about 16179.2133615946. The cubic root of 261766945 is about 639.6930046194.

The spelling of 261766945 in words is "two hundred sixty-one million, seven hundred sixty-six thousand, nine hundred forty-five".