81204338 has 16 divisors (see below), whose sum is σ = 122971200. Its totient is φ = 40216176.

The previous prime is 81204311. The next prime is 81204341. The reversal of 81204338 is 83340218.

It is a happy number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 81204338.

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 7 ways as a sum of consecutive naturals, for example, 148181 + ... + 148727.

It is an arithmetic number, because the mean of its divisors is an integer number (7685700).

Almost surely, 2^81204338 is an apocalyptic number.

81204338 is a deficient number, since it is larger than the sum of its proper divisors (41766862).

81204338 is a wasteful number, since it uses less digits than its factorization.

81204338 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1121.

The product of its (nonzero) digits is 4608, while the sum is 29.

The square root of 81204338 is about 9011.3449606593. The cubic root of 81204338 is about 433.0384006252.

The spelling of 81204338 in words is "eighty-one million, two hundred four thousand, three hundred thirty-eight".