261045403 has 4 divisors (see below), whose sum is σ = 263038248. Its totient is φ = 259052560.

The previous prime is 261045383. The next prime is 261045461. The reversal of 261045403 is 304540162.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 304540162 = 2 ⋅152270081.

It is a cyclic number.

It is not a de Polignac number, because 261045403 - 2⁵ = 261045371 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (261045703) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 996226 + ... + 996487.

It is an arithmetic number, because the mean of its divisors is an integer number (65759562).

Almost surely, 2^261045403 is an apocalyptic number.

261045403 is a deficient number, since it is larger than the sum of its proper divisors (1992845).

261045403 is a wasteful number, since it uses less digits than its factorization.

261045403 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1992844.

The product of its (nonzero) digits is 2880, while the sum is 25.

The square root of 261045403 is about 16156.8995478712. The cubic root of 261045403 is about 639.1047076373.

Adding to 261045403 its reverse (304540162), we get a palindrome (565585565).

The spelling of 261045403 in words is "two hundred sixty-one million, forty-five thousand, four hundred three".