81147206 has 8 divisors (see below), whose sum is σ = 139109520. Its totient is φ = 34777368.

The previous prime is 81147203. The next prime is 81147217. The reversal of 81147206 is 60274118.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81147203) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2898101 + ... + 2898128.

It is an arithmetic number, because the mean of its divisors is an integer number (17388690).

Almost surely, 2^81147206 is an apocalyptic number.

81147206 is a deficient number, since it is larger than the sum of its proper divisors (57962314).

81147206 is a wasteful number, since it uses less digits than its factorization.

81147206 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5796238.

The product of its (nonzero) digits is 2688, while the sum is 29.

The square root of 81147206 is about 9008.1743988446. The cubic root of 81147206 is about 432.9368208538.

The spelling of 81147206 in words is "eighty-one million, one hundred forty-seven thousand, two hundred six".