261745853 has 4 divisors (see below), whose sum is σ = 266684508. Its totient is φ = 256807200.

The previous prime is 261745837. The next prime is 261745871. The reversal of 261745853 is 358547162.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 235254244 + 26491609 = 15338^2 + 5147^2 .

It is a cyclic number.

It is not a de Polignac number, because 261745853 - 2⁴ = 261745837 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 261745853.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261745873) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2469248 + ... + 2469353.

It is an arithmetic number, because the mean of its divisors is an integer number (66671127).

Almost surely, 2^261745853 is an apocalyptic number.

It is an amenable number.

261745853 is a deficient number, since it is larger than the sum of its proper divisors (4938655).

261745853 is an equidigital number, since it uses as much as digits as its factorization.

261745853 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4938654.

The product of its digits is 201600, while the sum is 41.

The square root of 261745853 is about 16178.5615244372. The cubic root of 261745853 is about 639.6758229654.

The spelling of 261745853 in words is "two hundred sixty-one million, seven hundred forty-five thousand, eight hundred fifty-three".