81121130061 has 32 divisors (see below), whose sum is σ = 110851952640. Its totient is φ = 52753244544.

The previous prime is 81121130039. The next prime is 81121130081. The reversal of 81121130061 is 16003112118.

It is not a de Polignac number, because 81121130061 - 2⁶ = 81121129997 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81121130081) 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, 21810760 + ... + 21814478.

It is an arithmetic number, because the mean of its divisors is an integer number (3464123520).

Almost surely, 2^81121130061 is an apocalyptic number.

It is an amenable number.

81121130061 is a deficient number, since it is larger than the sum of its proper divisors (29730822579).

81121130061 is a wasteful number, since it uses less digits than its factorization.

81121130061 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4865.

The product of its (nonzero) digits is 288, while the sum is 24.

Adding to 81121130061 its reverse (16003112118), we get a palindrome (97124242179).

The spelling of 81121130061 in words is "eighty-one billion, one hundred twenty-one million, one hundred thirty thousand, sixty-one".