81429560 has 64 divisors (see below), whose sum is σ = 191358720. Its totient is φ = 31150080.

The previous prime is 81429559. The next prime is 81429581. The reversal of 81429560 is 6592418.

It is a self number, because there is not a number n which added to its sum of digits gives 81429560.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 119942 + ... + 120618.

It is an arithmetic number, because the mean of its divisors is an integer number (2989980).

Almost surely, 2^81429560 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 81429560, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (95679360).

81429560 is an abundant number, since it is smaller than the sum of its proper divisors (109929160).

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

81429560 is a wasteful number, since it uses less digits than its factorization.

81429560 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 816 (or 812 counting only the distinct ones).

The product of its (nonzero) digits is 17280, while the sum is 35.

The square root of 81429560 is about 9023.8328885236. The cubic root of 81429560 is about 433.4383782157.

The spelling of 81429560 in words is "eighty-one million, four hundred twenty-nine thousand, five hundred sixty".