81336042 has 16 divisors (see below), whose sum is σ = 180746880. Its totient is φ = 27111996.

The previous prime is 81336029. The next prime is 81336061. The reversal of 81336042 is 24063318.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a junction number, because it is equal to n+sod(n) for n = 81335997 and 81336015.

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, 753058 + ... + 753165.

It is an arithmetic number, because the mean of its divisors is an integer number (11296680).

Almost surely, 2^81336042 is an apocalyptic number.

81336042 is an abundant number, since it is smaller than the sum of its proper divisors (99410838).

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

81336042 is a wasteful number, since it uses less digits than its factorization.

81336042 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1506234 (or 1506228 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 27.

The square root of 81336042 is about 9018.6496771967. The cubic root of 81336042 is about 433.2723868263.

The spelling of 81336042 in words is "eighty-one million, three hundred thirty-six thousand, forty-two".