81907153730 has 8 divisors (see below), whose sum is σ = 147432876732. Its totient is φ = 32762861488.

The previous prime is 81907153729. The next prime is 81907153771. The reversal of 81907153730 is 3735170918.

It can be written as a sum of positive squares in 2 ways, for example, as 79754843281 + 2152310449 = 282409^2 + 46393^2 .

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

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, 4095357677 + ... + 4095357696.

Almost surely, 2^81907153730 is an apocalyptic number.

81907153730 is a deficient number, since it is larger than the sum of its proper divisors (65525723002).

81907153730 is a wasteful number, since it uses less digits than its factorization.

81907153730 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8190715380.

The product of its (nonzero) digits is 158760, while the sum is 44.

The spelling of 81907153730 in words is "eighty-one billion, nine hundred seven million, one hundred fifty-three thousand, seven hundred thirty".