81228705042 has 16 divisors (see below), whose sum is σ = 162461400192. Its totient is φ = 27075570000.

The previous prime is 81228705037. The next prime is 81228705053. The reversal of 81228705042 is 24050782218.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 142503 + ... + 427509.

It is an arithmetic number, because the mean of its divisors is an integer number (10153837512).

Almost surely, 2^81228705042 is an apocalyptic number.

It is a pronic number, being equal to 285006×285007.

81228705042 is an abundant number, since it is smaller than the sum of its proper divisors (81232695150).

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

81228705042 is a wasteful number, since it uses less digits than its factorization.

81228705042 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 332513.

The product of its (nonzero) digits is 71680, while the sum is 39.

The spelling of 81228705042 in words is "eighty-one billion, two hundred twenty-eight million, seven hundred five thousand, forty-two".