261421062543353 has 4 divisors (see below), whose sum is σ = 261421108121460. Its totient is φ = 261421016965248.

The previous prime is 261421062543349. The next prime is 261421062543437. The reversal of 261421062543353 is 353345260124162.

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 86000918174224 + 175420144369129 = 9273668^2 + 13244627^2 .

It is a cyclic number.

It is not a de Polignac number, because 261421062543353 - 2² = 261421062543349 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 261421062543298 and 261421062543307.

It is not an unprimeable number, because it can be changed into a prime (261421062743353) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 12695300 + ... + 26153637.

It is an arithmetic number, because the mean of its divisors is an integer number (65355277030365).

Almost surely, 2^{261421062543353} is an apocalyptic number.

It is an amenable number.

261421062543353 is a deficient number, since it is larger than the sum of its proper divisors (45578107).

261421062543353 is an equidigital number, since it uses as much as digits as its factorization.

261421062543353 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 45578106.

The product of its (nonzero) digits is 3110400, while the sum is 47.

The spelling of 261421062543353 in words is "two hundred sixty-one trillion, four hundred twenty-one billion, sixty-two million, five hundred forty-three thousand, three hundred fifty-three".