81455555 has 8 divisors (see below), whose sum is σ = 97807344. Its totient is φ = 65124000.

The previous prime is 81455533. The next prime is 81455567. The reversal of 81455555 is 55555418.

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

It is not a de Polignac number, because 81455555 - 2¹⁶ = 81390019 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6005 + ... + 14105.

It is an arithmetic number, because the mean of its divisors is an integer number (12225918).

Almost surely, 2^81455555 is an apocalyptic number.

81455555 is a deficient number, since it is larger than the sum of its proper divisors (16351789).

81455555 is a wasteful number, since it uses less digits than its factorization.

81455555 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10117.

The product of its digits is 100000, while the sum is 38.

The square root of 81455555 is about 9025.2731260611. The cubic root of 81455555 is about 433.4844959150.

The spelling of 81455555 in words is "eighty-one million, four hundred fifty-five thousand, five hundred fifty-five".