81547805730 has 32 divisors (see below), whose sum is σ = 196207746624. Its totient is φ = 21691302336.

The previous prime is 81547805719. The next prime is 81547805753. The reversal of 81547805730 is 3750874518.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 81547805730.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3411592 + ... + 3435411.

It is an arithmetic number, because the mean of its divisors is an integer number (6131492082).

Almost surely, 2^81547805730 is an apocalyptic number.

81547805730 is an abundant number, since it is smaller than the sum of its proper divisors (114659940894).

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

81547805730 is a wasteful number, since it uses less digits than its factorization.

81547805730 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6847410.

The product of its (nonzero) digits is 940800, while the sum is 48.

The spelling of 81547805730 in words is "eighty-one billion, five hundred forty-seven million, eight hundred five thousand, seven hundred thirty".