81522479 has 8 divisors (see below), whose sum is σ = 82356912. Its totient is φ = 80691520.

The previous prime is 81522461. The next prime is 81522499. The reversal of 81522479 is 97422518.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 81522479 - 2⁸ = 81522223 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81522449) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 85067 + ... + 86019.

It is an arithmetic number, because the mean of its divisors is an integer number (10294614).

Almost surely, 2^81522479 is an apocalyptic number.

81522479 is a deficient number, since it is larger than the sum of its proper divisors (834433).

81522479 is a wasteful number, since it uses less digits than its factorization.

81522479 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1737.

The product of its digits is 40320, while the sum is 38.

The square root of 81522479 is about 9028.9799534610. The cubic root of 81522479 is about 433.6031805769.

The spelling of 81522479 in words is "eighty-one million, five hundred twenty-two thousand, four hundred seventy-nine".