81659422 has 16 divisors (see below), whose sum is σ = 134149680. Its totient is φ = 37049472.

The previous prime is 81659411. The next prime is 81659429. The reversal of 81659422 is 22495618.

It is a super-2 number, since 2×81659422² = 13336522402748168, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81659429) 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, 25083 + ... + 28150.

It is an arithmetic number, because the mean of its divisors is an integer number (8384355).

Almost surely, 2^81659422 is an apocalyptic number.

81659422 is a deficient number, since it is larger than the sum of its proper divisors (52490258).

81659422 is a wasteful number, since it uses less digits than its factorization.

81659422 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 53307.

The product of its digits is 34560, while the sum is 37.

The square root of 81659422 is about 9036.5602969271. The cubic root of 81659422 is about 433.8458363591.

The spelling of 81659422 in words is "eighty-one million, six hundred fifty-nine thousand, four hundred twenty-two".