81324706 has 4 divisors (see below), whose sum is σ = 121987062. Its totient is φ = 40662352.

The previous prime is 81324697. The next prime is 81324709. The reversal of 81324706 is 60742318.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 63760225 + 17564481 = 7985^2 + 4191^2 .

It is a super-2 number, since 2×81324706² = 13227415611972872, which contains 22 as substring.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is not an unprimeable number, because it can be changed into a prime (81324709) 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 as a sum of consecutive naturals, namely, 20331175 + ... + 20331178.

Almost surely, 2^81324706 is an apocalyptic number.

81324706 is a deficient number, since it is larger than the sum of its proper divisors (40662356).

81324706 is a wasteful number, since it uses less digits than its factorization.

81324706 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40662355.

The product of its (nonzero) digits is 8064, while the sum is 31.

The square root of 81324706 is about 9018.0211798376. The cubic root of 81324706 is about 433.2522571525.

The spelling of 81324706 in words is "eighty-one million, three hundred twenty-four thousand, seven hundred six".