261254605 has 16 divisors (see below), whose sum is σ = 318427200. Its totient is φ = 205744000.

The previous prime is 261254603. The next prime is 261254611. The reversal of 261254605 is 506452162.

It is not a de Polignac number, because 261254605 - 2¹ = 261254603 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261254603) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 110526 + ... + 112864.

It is an arithmetic number, because the mean of its divisors is an integer number (19901700).

Almost surely, 2^261254605 is an apocalyptic number.

It is an amenable number.

261254605 is a deficient number, since it is larger than the sum of its proper divisors (57172595).

261254605 is a wasteful number, since it uses less digits than its factorization.

261254605 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2684.

The product of its (nonzero) digits is 14400, while the sum is 31.

The square root of 261254605 is about 16163.3723275807. The cubic root of 261254605 is about 639.2753883964.

The spelling of 261254605 in words is "two hundred sixty-one million, two hundred fifty-four thousand, six hundred five".