261043403 has 4 divisors (see below), whose sum is σ = 261544968. Its totient is φ = 260541840.

The previous prime is 261043379. The next prime is 261043423. The reversal of 261043403 is 304340162.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 261043403 - 2¹⁸ = 260781259 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (261043423) 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 3 ways as a sum of consecutive naturals, for example, 250001 + ... + 251042.

It is an arithmetic number, because the mean of its divisors is an integer number (65386242).

Almost surely, 2^261043403 is an apocalyptic number.

261043403 is a deficient number, since it is larger than the sum of its proper divisors (501565).

261043403 is an equidigital number, since it uses as much as digits as its factorization.

261043403 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 501564.

The product of its (nonzero) digits is 1728, while the sum is 23.

The square root of 261043403 is about 16156.8376546897. The cubic root of 261043403 is about 639.1030754657.

Adding to 261043403 its reverse (304340162), we get a palindrome (565383565).

The spelling of 261043403 in words is "two hundred sixty-one million, forty-three thousand, four hundred three".