81520327 has 4 divisors (see below), whose sum is σ = 93166096. Its totient is φ = 69874560.

The previous prime is 81520319. The next prime is 81520331. The reversal of 81520327 is 72302518.

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

It is not a de Polignac number, because 81520327 - 2³ = 81520319 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 81520295 and 81520304.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81520367) 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, 5822874 + ... + 5822887.

It is an arithmetic number, because the mean of its divisors is an integer number (23291524).

Almost surely, 2^81520327 is an apocalyptic number.

81520327 is a deficient number, since it is larger than the sum of its proper divisors (11645769).

81520327 is a wasteful number, since it uses less digits than its factorization.

81520327 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11645768.

The product of its (nonzero) digits is 3360, while the sum is 28.

The square root of 81520327 is about 9028.8607808516. The cubic root of 81520327 is about 433.5993651783.

The spelling of 81520327 in words is "eighty-one million, five hundred twenty thousand, three hundred twenty-seven".