81385942 has 16 divisors (see below), whose sum is σ = 133440192. Its totient is φ = 36920520.

The previous prime is 81385939. The next prime is 81385963. The reversal of 81385942 is 24958318.

It is a junction number, because it is equal to n+sod(n) for n = 81385895 and 81385904.

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, 8653 + ... + 15415.

It is an arithmetic number, because the mean of its divisors is an integer number (8340012).

Almost surely, 2^81385942 is an apocalyptic number.

81385942 is a deficient number, since it is larger than the sum of its proper divisors (52054250).

81385942 is a wasteful number, since it uses less digits than its factorization.

81385942 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7323.

The product of its digits is 69120, while the sum is 40.

The square root of 81385942 is about 9021.4157425539. The cubic root of 81385942 is about 433.3609735164.

The spelling of 81385942 in words is "eighty-one million, three hundred eighty-five thousand, nine hundred forty-two".