81555567530 has 8 divisors (see below), whose sum is σ = 146800021572. Its totient is φ = 32622227008.

The previous prime is 81555567523. The next prime is 81555567547. The reversal of 81555567530 is 3576555518.

It can be written as a sum of positive squares in 2 ways, for example, as 80652024049 + 903543481 = 283993^2 + 30059^2 .

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

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4077778367 + ... + 4077778386.

Almost surely, 2^81555567530 is an apocalyptic number.

81555567530 is a deficient number, since it is larger than the sum of its proper divisors (65244454042).

81555567530 is a wasteful number, since it uses less digits than its factorization.

81555567530 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8155556760.

The product of its (nonzero) digits is 3150000, while the sum is 50.

The spelling of 81555567530 in words is "eighty-one billion, five hundred fifty-five million, five hundred sixty-seven thousand, five hundred thirty".