261958045 has 4 divisors (see below), whose sum is σ = 314349660. Its totient is φ = 209566432.

The previous prime is 261958013. The next prime is 261958051. The reversal of 261958045 is 540859162.

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 56580484 + 205377561 = 7522^2 + 14331^2 .

It is a cyclic number.

It is not a de Polignac number, because 261958045 - 2⁵ = 261958013 is a prime.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a junction number, because it is equal to n+sod(n) for n = 261957989 and 261958007.

It is a congruent number.

It is an unprimeable number.

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, 26195800 + ... + 26195809.

It is an arithmetic number, because the mean of its divisors is an integer number (78587415).

Almost surely, 2^261958045 is an apocalyptic number.

It is an amenable number.

261958045 is a deficient number, since it is larger than the sum of its proper divisors (52391615).

261958045 is an equidigital number, since it uses as much as digits as its factorization.

261958045 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 52391614.

The product of its (nonzero) digits is 86400, while the sum is 40.

The square root of 261958045 is about 16185.1180100733. The cubic root of 261958045 is about 639.8486336368.

The spelling of 261958045 in words is "two hundred sixty-one million, nine hundred fifty-eight thousand, forty-five".