81149170730 has 8 divisors (see below), whose sum is σ = 146068507332. Its totient is φ = 32459668288.

The previous prime is 81149170721. The next prime is 81149170741. The reversal of 81149170730 is 3707194118.

It can be written as a sum of positive squares in 2 ways, for example, as 77607373561 + 3541797169 = 278581^2 + 59513^2 .

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

It is a Curzon number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4057458527 + ... + 4057458546.

Almost surely, 2^81149170730 is an apocalyptic number.

81149170730 is a deficient number, since it is larger than the sum of its proper divisors (64919336602).

81149170730 is a wasteful number, since it uses less digits than its factorization.

81149170730 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8114917080.

The product of its (nonzero) digits is 42336, while the sum is 41.

The spelling of 81149170730 in words is "eighty-one billion, one hundred forty-nine million, one hundred seventy thousand, seven hundred thirty".