81479860 has 96 divisors (see below), whose sum is σ = 215324928. Its totient is φ = 25159680.

The previous prime is 81479857. The next prime is 81479863. The reversal of 81479860 is 6897418.

It is an interprime number because it is at equal distance from previous prime (81479857) and next prime (81479863).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81479863) 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 31 ways as a sum of consecutive naturals, for example, 241612 + ... + 241948.

It is an arithmetic number, because the mean of its divisors is an integer number (2242968).

Almost surely, 2^81479860 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81479860, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (107662464).

81479860 is an abundant number, since it is smaller than the sum of its proper divisors (133845068).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

81479860 is a wasteful number, since it uses less digits than its factorization.

81479860 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 521 (or 519 counting only the distinct ones).

The product of its (nonzero) digits is 96768, while the sum is 43.

The square root of 81479860 is about 9026.6195222796. The cubic root of 81479860 is about 433.5276065125.

The spelling of 81479860 in words is "eighty-one million, four hundred seventy-nine thousand, eight hundred sixty".