261631235447 has 2 divisors, whose sum is σ = 261631235448. Its totient is φ = 261631235446.

The previous prime is 261631235413. The next prime is 261631235519. The reversal of 261631235447 is 744532136162.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 261631235447 - 2⁸ = 261631235191 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 261631235398 and 261631235407.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (261631235947) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 130815617723 + 130815617724.

It is an arithmetic number, because the mean of its divisors is an integer number (130815617724).

Almost surely, 2^261631235447 is an apocalyptic number.

261631235447 is a deficient number, since it is larger than the sum of its proper divisors (1).

261631235447 is an equidigital number, since it uses as much as digits as its factorization.

261631235447 is an evil number, because the sum of its binary digits is even.

The product of its digits is 725760, while the sum is 44.

The spelling of 261631235447 in words is "two hundred sixty-one billion, six hundred thirty-one million, two hundred thirty-five thousand, four hundred forty-seven".