81621483 has 4 divisors (see below), whose sum is σ = 108828648. Its totient is φ = 54414320.

The previous prime is 81621479. The next prime is 81621493. The reversal of 81621483 is 38412618.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 81621483 - 2² = 81621479 is a prime.

It is not an unprimeable number, because it can be changed into a prime (81621413) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13603578 + ... + 13603583.

It is an arithmetic number, because the mean of its divisors is an integer number (27207162).

Almost surely, 2^81621483 is an apocalyptic number.

81621483 is a deficient number, since it is larger than the sum of its proper divisors (27207165).

81621483 is a wasteful number, since it uses less digits than its factorization.

81621483 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27207164.

The product of its digits is 9216, while the sum is 33.

The square root of 81621483 is about 9034.4608582914. The cubic root of 81621483 is about 433.7786376350.

The spelling of 81621483 in words is "eighty-one million, six hundred twenty-one thousand, four hundred eighty-three".