81008542 has 16 divisors (see below), whose sum is σ = 128381760. Its totient is φ = 38274208.

The previous prime is 81008509. The next prime is 81008569. The reversal of 81008542 is 24580018.

It is a self number, because there is not a number n which added to its sum of digits gives 81008542.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 12133 + ... + 17584.

It is an arithmetic number, because the mean of its divisors is an integer number (8023860).

Almost surely, 2^81008542 is an apocalyptic number.

81008542 is a deficient number, since it is larger than the sum of its proper divisors (47373218).

81008542 is a wasteful number, since it uses less digits than its factorization.

81008542 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 29795.

The product of its (nonzero) digits is 2560, while the sum is 28.

The square root of 81008542 is about 9000.4745430449. The cubic root of 81008542 is about 432.6900800586.

The spelling of 81008542 in words is "eighty-one million, eight thousand, five hundred forty-two".