261125013 has 4 divisors (see below), whose sum is σ = 348166688. Its totient is φ = 174083340.

The previous prime is 261124987. The next prime is 261125027. The reversal of 261125013 is 310521162.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 261125013 - 2²⁶ = 194016149 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261121013) 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, 43520833 + ... + 43520838.

It is an arithmetic number, because the mean of its divisors is an integer number (87041672).

Almost surely, 2^261125013 is an apocalyptic number.

It is an amenable number.

261125013 is a deficient number, since it is larger than the sum of its proper divisors (87041675).

261125013 is an equidigital number, since it uses as much as digits as its factorization.

261125013 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 87041674.

The product of its (nonzero) digits is 360, while the sum is 21.

The square root of 261125013 is about 16159.3630134359. The cubic root of 261125013 is about 639.1696694586.

Adding to 261125013 its reverse (310521162), we get a palindrome (571646175).

It can be divided in two parts, 26112 and 5013, that added together give a triangular number (31125 = T₂₄₉).

The spelling of 261125013 in words is "two hundred sixty-one million, one hundred twenty-five thousand, thirteen".