81373842 has 32 divisors (see below), whose sum is σ = 197271360. Its totient is φ = 24658560.

The previous prime is 81373829. The next prime is 81373843. The reversal of 81373842 is 24837318.

It is a junction number, because it is equal to n+sod(n) for n = 81373797 and 81373806.

It is not an unprimeable number, because it can be changed into a prime (81373843) 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 15 ways as a sum of consecutive naturals, for example, 67903 + ... + 69090.

It is an arithmetic number, because the mean of its divisors is an integer number (6164730).

Almost surely, 2^81373842 is an apocalyptic number.

81373842 is an abundant number, since it is smaller than the sum of its proper divisors (115897518).

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

81373842 is a wasteful number, since it uses less digits than its factorization.

81373842 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 137015 (or 137009 counting only the distinct ones).

The product of its digits is 32256, while the sum is 36.

The square root of 81373842 is about 9020.7450911773. The cubic root of 81373842 is about 433.3394959018.

It can be divided in two parts, 81373 and 842, that added together give a triangular number (82215 = T₄₀₅).

The spelling of 81373842 in words is "eighty-one million, three hundred seventy-three thousand, eight hundred forty-two".