81051912 has 36 divisors (see below), whose sum is σ = 219722685. Its totient is φ = 26991840.

The previous prime is 81051881. The next prime is 81051953. The reversal of 81051912 is 21915018.

It is a powerful number, because all its prime factors have an exponent greater than 1 and also an Achilles number because it is not a perfect power.

It can be written as a sum of positive squares in 2 ways, for example, as 78960996 + 2090916 = 8886^2 + 1446^2 .

It is a tau number, because it is divible by the number of its divisors (36).

It is an ABA number since it can be written as A⋅B^A, here for A=2, B=6366.

It is an unprimeable number.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 75862 + ... + 76922.

Almost surely, 2^81051912 is an apocalyptic number.

It is an amenable number.

81051912 is an abundant number, since it is smaller than the sum of its proper divisors (138670773).

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

81051912 is a wasteful number, since it uses less digits than its factorization.

81051912 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2134 (or 1066 counting only the distinct ones).

The product of its (nonzero) digits is 720, while the sum is 27.

The square root of 81051912 is about 9002.8835380671. The cubic root of 81051912 is about 432.7672835255.

The spelling of 81051912 in words is "eighty-one million, fifty-one thousand, nine hundred twelve".