81627972 has 12 divisors (see below), whose sum is σ = 190465296. Its totient is φ = 27209320.

The previous prime is 81627967. The next prime is 81627983. The reversal of 81627972 is 27972618.

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

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 3 ways as a sum of consecutive naturals, for example, 3401154 + ... + 3401177.

It is an arithmetic number, because the mean of its divisors is an integer number (15872108).

Almost surely, 2^81627972 is an apocalyptic number.

It is an amenable number.

81627972 is an abundant number, since it is smaller than the sum of its proper divisors (108837324).

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

81627972 is a wasteful number, since it uses less digits than its factorization.

81627972 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6802338 (or 6802336 counting only the distinct ones).

The product of its digits is 84672, while the sum is 42.

The square root of 81627972 is about 9034.8199760704. The cubic root of 81627972 is about 433.7901326275.

The spelling of 81627972 in words is "eighty-one million, six hundred twenty-seven thousand, nine hundred seventy-two".