81422599 has 8 divisors (see below), whose sum is σ = 85243392. Its totient is φ = 77625240.

The previous prime is 81422557. The next prime is 81422609. The reversal of 81422599 is 99522418.

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 81422599 - 2¹³ = 81414407 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 (81422519) 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 7 ways as a sum of consecutive naturals, for example, 1462 + ... + 12844.

It is an arithmetic number, because the mean of its divisors is an integer number (10655424).

Almost surely, 2^81422599 is an apocalyptic number.

81422599 is a deficient number, since it is larger than the sum of its proper divisors (3820793).

81422599 is a wasteful number, since it uses less digits than its factorization.

81422599 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11717.

The product of its digits is 51840, while the sum is 40.

The square root of 81422599 is about 9023.4471794320. The cubic root of 81422599 is about 433.4260270477.

The spelling of 81422599 in words is "eighty-one million, four hundred twenty-two thousand, five hundred ninety-nine".