81223986 has 16 divisors (see below), whose sum is σ = 162549504. Its totient is φ = 27057744.

The previous prime is 81223969. The next prime is 81223997. The reversal of 81223986 is 68932218.

It is a happy number.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 9700 + ... + 16016.

It is an arithmetic number, because the mean of its divisors is an integer number (10159344).

Almost surely, 2^81223986 is an apocalyptic number.

81223986 is an abundant number, since it is smaller than the sum of its proper divisors (81325518).

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

81223986 is a wasteful number, since it uses less digits than its factorization.

81223986 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8465.

The product of its digits is 41472, while the sum is 39.

The square root of 81223986 is about 9012.4350760491. The cubic root of 81223986 is about 433.0733234408.

The spelling of 81223986 in words is "eighty-one million, two hundred twenty-three thousand, nine hundred eighty-six".