81582612 has 12 divisors (see below), whose sum is σ = 190359456. Its totient is φ = 27194200.

The previous prime is 81582601. The next prime is 81582619. The reversal of 81582612 is 21628518.

It is a tau number, because it is divible by the number of its divisors (12).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81582619) 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 in 3 ways as a sum of consecutive naturals, for example, 3399264 + ... + 3399287.

It is an arithmetic number, because the mean of its divisors is an integer number (15863288).

Almost surely, 2^81582612 is an apocalyptic number.

It is an amenable number.

81582612 is an abundant number, since it is smaller than the sum of its proper divisors (108776844).

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

81582612 is a wasteful number, since it uses less digits than its factorization.

81582612 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6798558 (or 6798556 counting only the distinct ones).

The product of its digits is 7680, while the sum is 33.

The square root of 81582612 is about 9032.3093392554. The cubic root of 81582612 is about 433.7097665234.

The spelling of 81582612 in words is "eighty-one million, five hundred eighty-two thousand, six hundred twelve".