81583012 has 24 divisors (see below), whose sum is σ = 164669120. Its totient is φ = 34642080.

The previous prime is 81582971. The next prime is 81583027. The reversal of 81583012 is 21038518.

It is a Harshad number since it is a multiple of its sum of digits (28).

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10314 + ... + 16417.

Almost surely, 2^81583012 is an apocalyptic number.

It is an amenable number.

81583012 is an abundant number, since it is smaller than the sum of its proper divisors (83086108).

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

81583012 is a wasteful number, since it uses less digits than its factorization.

81583012 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26851 (or 26849 counting only the distinct ones).

The product of its (nonzero) digits is 1920, while the sum is 28.

The square root of 81583012 is about 9032.3314819597. The cubic root of 81583012 is about 433.7104753494.

The spelling of 81583012 in words is "eighty-one million, five hundred eighty-three thousand, twelve".