261141945 has 16 divisors (see below), whose sum is σ = 422136960. Its totient is φ = 137839104.

The previous prime is 261141919. The next prime is 261141961. The reversal of 261141945 is 549141162.

It is not a de Polignac number, because 261141945 - 2¹¹ = 261139897 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 88285 + ... + 91194.

It is an arithmetic number, because the mean of its divisors is an integer number (26383560).

Almost surely, 2^261141945 is an apocalyptic number.

It is an amenable number.

261141945 is a deficient number, since it is larger than the sum of its proper divisors (160995015).

261141945 is a wasteful number, since it uses less digits than its factorization.

261141945 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 179584.

The product of its digits is 8640, while the sum is 33.

The square root of 261141945 is about 16159.8869117330. The cubic root of 261141945 is about 639.1834842809.

The spelling of 261141945 in words is "two hundred sixty-one million, one hundred forty-one thousand, nine hundred forty-five".