261031431135 has 32 divisors (see below), whose sum is σ = 421213201920. Its totient is φ = 138031786368.

The previous prime is 261031431131. The next prime is 261031431151. The reversal of 261031431135 is 531134130162.

It is not a de Polignac number, because 261031431135 - 2² = 261031431131 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261031431131) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1495654 + ... + 1661036.

It is an arithmetic number, because the mean of its divisors is an integer number (13162912560).

Almost surely, 2^261031431135 is an apocalyptic number.

261031431135 is a deficient number, since it is larger than the sum of its proper divisors (160181770785).

261031431135 is a wasteful number, since it uses less digits than its factorization.

261031431135 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 166287.

The product of its (nonzero) digits is 6480, while the sum is 30.

Adding to 261031431135 its reverse (531134130162), we get a palindrome (792165561297).

The spelling of 261031431135 in words is "two hundred sixty-one billion, thirty-one million, four hundred thirty-one thousand, one hundred thirty-five".