81376128 has 48 divisors (see below), whose sum is σ = 234171600. Its totient is φ = 27124992.

The previous prime is 81376121. The next prime is 81376189. The reversal of 81376128 is 82167318.

81376128 is a `hidden beast` number, since 8 + 1 + 37 + 612 + 8 = 666.

It is a tau number, because it is divible by the number of its divisors (48).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 81376092 and 81376101.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81376121) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 34168 + ... + 36471.

It is an arithmetic number, because the mean of its divisors is an integer number (4878575).

Almost surely, 2^81376128 is an apocalyptic number.

It is an amenable number.

81376128 is an abundant number, since it is smaller than the sum of its proper divisors (152795472).

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

81376128 is a wasteful number, since it uses less digits than its factorization.

81376128 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 70659 (or 70644 counting only the distinct ones).

The product of its digits is 16128, while the sum is 36.

The square root of 81376128 is about 9020.8717982244. The cubic root of 81376128 is about 433.3435537366.

The spelling of 81376128 in words is "eighty-one million, three hundred seventy-six thousand, one hundred twenty-eight".