81196542 has 48 divisors (see below), whose sum is σ = 205350912. Its totient is φ = 22703760.

The previous prime is 81196541. The next prime is 81196543. The reversal of 81196542 is 24569118.

It is an interprime number because it is at equal distance from previous prime (81196541) and next prime (81196543).

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 81196497 and 81196506.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81196541) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 934 + ... + 12777.

It is an arithmetic number, because the mean of its divisors is an integer number (4278144).

Almost surely, 2^81196542 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81196542, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (102675456).

81196542 is an abundant number, since it is smaller than the sum of its proper divisors (124154370).

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

81196542 is a wasteful number, since it uses less digits than its factorization.

81196542 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13773 (or 13770 counting only the distinct ones).

The product of its digits is 17280, while the sum is 36.

The square root of 81196542 is about 9010.9123844370. The cubic root of 81196542 is about 433.0245422710.

The spelling of 81196542 in words is "eighty-one million, one hundred ninety-six thousand, five hundred forty-two".