81126712 has 8 divisors (see below), whose sum is σ = 152112600. Its totient is φ = 40563352.

The previous prime is 81126709. The next prime is 81126733. The reversal of 81126712 is 21762118.

It is a tau number, because it is divible by the number of its divisors (8).

It is a hoax number, since the sum of its digits (28) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5070412 + ... + 5070427.

It is an arithmetic number, because the mean of its divisors is an integer number (19014075).

Almost surely, 2^81126712 is an apocalyptic number.

It is an amenable number.

81126712 is a deficient number, since it is larger than the sum of its proper divisors (70985888).

81126712 is a wasteful number, since it uses less digits than its factorization.

81126712 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10140845 (or 10140841 counting only the distinct ones).

The product of its digits is 1344, while the sum is 28.

The square root of 81126712 is about 9007.0368046323. The cubic root of 81126712 is about 432.9003712347.

The spelling of 81126712 in words is "eighty-one million, one hundred twenty-six thousand, seven hundred twelve".