81933216 has 48 divisors (see below), whose sum is σ = 215568864. Its totient is φ = 27248384.

The previous prime is 81933197. The next prime is 81933233. The reversal of 81933216 is 61233918.

It is a tau number, because it is divible by the number of its divisors (48).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 62035 + ... + 63341.

It is an arithmetic number, because the mean of its divisors is an integer number (4491018).

Almost surely, 2^81933216 is an apocalyptic number.

It is an amenable number.

81933216 is an abundant number, since it is smaller than the sum of its proper divisors (133635648).

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

81933216 is a wasteful number, since it uses less digits than its factorization.

81933216 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1973 (or 1965 counting only the distinct ones).

The product of its digits is 7776, while the sum is 33.

The square root of 81933216 is about 9051.6968574958. The cubic root of 81933216 is about 434.3301727009.

The spelling of 81933216 in words is "eighty-one million, nine hundred thirty-three thousand, two hundred sixteen".