81204042 has 8 divisors (see below), whose sum is σ = 162408096. Its totient is φ = 27068012.

The previous prime is 81204041. The next prime is 81204047. The reversal of 81204042 is 24040218.

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

81204042 is an admirable number.

It is not an unprimeable number, because it can be changed into a prime (81204041) 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 3 ways as a sum of consecutive naturals, for example, 6766998 + ... + 6767009.

It is an arithmetic number, because the mean of its divisors is an integer number (20301012).

Almost surely, 2^81204042 is an apocalyptic number.

81204042 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

81204042 is a wasteful number, since it uses less digits than its factorization.

81204042 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13534012.

The product of its (nonzero) digits is 512, while the sum is 21.

The square root of 81204042 is about 9011.3285369029. The cubic root of 81204042 is about 433.0378744647.

The spelling of 81204042 in words is "eighty-one million, two hundred four thousand, forty-two".