81845542 has 8 divisors (see below), whose sum is σ = 122943600. Its totient is φ = 40864344.

The previous prime is 81845539. The next prime is 81845573. The reversal of 81845542 is 24554818.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a congruent number.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 27442 + ... + 30277.

It is an arithmetic number, because the mean of its divisors is an integer number (15367950).

Almost surely, 2^81845542 is an apocalyptic number.

81845542 is a deficient number, since it is larger than the sum of its proper divisors (41098058).

81845542 is a wasteful number, since it uses less digits than its factorization.

81845542 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 58430.

The product of its digits is 51200, while the sum is 37.

The square root of 81845542 is about 9046.8526018721. The cubic root of 81845542 is about 434.1751966687.

It can be divided in two parts, 818 and 45542, that added together give a triangular number (46360 = T₃₀₄).

The spelling of 81845542 in words is "eighty-one million, eight hundred forty-five thousand, five hundred forty-two".