261631235443 has 4 divisors (see below), whose sum is σ = 261674941320. Its totient is φ = 261587529568.

The previous prime is 261631235413. The next prime is 261631235447. The reversal of 261631235443 is 344532136162.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-261631235443 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 261631235396 and 261631235405.

It is not an unprimeable number, because it can be changed into a prime (261631235447) 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, 21843958 + ... + 21855931.

It is an arithmetic number, because the mean of its divisors is an integer number (65418735330).

Almost surely, 2^261631235443 is an apocalyptic number.

261631235443 is a deficient number, since it is larger than the sum of its proper divisors (43705877).

261631235443 is an equidigital number, since it uses as much as digits as its factorization.

261631235443 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43705876.

The product of its digits is 311040, while the sum is 40.

The spelling of 261631235443 in words is "two hundred sixty-one billion, six hundred thirty-one million, two hundred thirty-five thousand, four hundred forty-three".