261234891 has 6 divisors (see below), whose sum is σ = 377339300. Its totient is φ = 174156588.

The previous prime is 261234889. The next prime is 261234893. The reversal of 261234891 is 198432162.

261234891 is a `hidden beast` number, since 2 + 612 + 34 + 8 + 9 + 1 = 666.

It is an interprime number because it is at equal distance from previous prime (261234889) and next prime (261234893).

It is not a de Polignac number, because 261234891 - 2¹ = 261234889 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (261234893) by changing a digit.

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 5 ways as a sum of consecutive naturals, for example, 14513041 + ... + 14513058.

Almost surely, 2^261234891 is an apocalyptic number.

261234891 is a deficient number, since it is larger than the sum of its proper divisors (116104409).

261234891 is a wasteful number, since it uses less digits than its factorization.

261234891 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29026105 (or 29026102 counting only the distinct ones).

The product of its digits is 20736, while the sum is 36.

The square root of 261234891 is about 16162.7624804673. The cubic root of 261234891 is about 639.2593083072.

The spelling of 261234891 in words is "two hundred sixty-one million, two hundred thirty-four thousand, eight hundred ninety-one".