81107929140 has 144 divisors (see below), whose sum is σ = 269801425152. Its totient is φ = 18144478464.

The previous prime is 81107929139. The next prime is 81107929159. The reversal of 81107929140 is 4192970118.

It is a super-2 number, since 2×81107929140² (a number of 23 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a junction number, because it is equal to n+sod(n) for n = 81107929092 and 81107929101.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 155307 + ... + 431666.

It is an arithmetic number, because the mean of its divisors is an integer number (1873621008).

Almost surely, 2^81107929140 is an apocalyptic number.

It is an amenable number.

81107929140 is an abundant number, since it is smaller than the sum of its proper divisors (188693496012).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

81107929140 is a wasteful number, since it uses less digits than its factorization.

81107929140 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 587046 (or 587037 counting only the distinct ones).

The product of its (nonzero) digits is 36288, while the sum is 42.

The spelling of 81107929140 in words is "eighty-one billion, one hundred seven million, nine hundred twenty-nine thousand, one hundred forty".