81824816 has 10 divisors (see below), whose sum is σ = 158535612. Its totient is φ = 40912400.

The previous prime is 81824783. The next prime is 81824819. The reversal of 81824816 is 61842818.

It is a self number, because there is not a number n which added to its sum of digits gives 81824816.

It is not an unprimeable number, because it can be changed into a prime (81824819) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2557010 + ... + 2557041.

Almost surely, 2^81824816 is an apocalyptic number.

It is an amenable number.

81824816 is a deficient number, since it is larger than the sum of its proper divisors (76710796).

81824816 is a wasteful number, since it uses less digits than its factorization.

81824816 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5114059 (or 5114053 counting only the distinct ones).

The product of its digits is 24576, while the sum is 38.

The square root of 81824816 is about 9045.7070480975. The cubic root of 81824816 is about 434.1385443983.

The spelling of 81824816 in words is "eighty-one million, eight hundred twenty-four thousand, eight hundred sixteen".