81054505 has 8 divisors (see below), whose sum is σ = 111160512. Its totient is φ = 55580208.

The previous prime is 81054469. The next prime is 81054509. The reversal of 81054505 is 50545018.

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

It is a cyclic number.

It is not a de Polignac number, because 81054505 - 2¹¹ = 81052457 is a prime.

It is an alternating number because its digits alternate between even and odd.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81054509) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1157887 + ... + 1157956.

It is an arithmetic number, because the mean of its divisors is an integer number (13895064).

Almost surely, 2^81054505 is an apocalyptic number.

It is an amenable number.

81054505 is a deficient number, since it is larger than the sum of its proper divisors (30106007).

81054505 is a wasteful number, since it uses less digits than its factorization.

81054505 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2315855.

The product of its (nonzero) digits is 4000, while the sum is 28.

The square root of 81054505 is about 9003.0275463313. The cubic root of 81054505 is about 432.7718984838.

The spelling of 81054505 in words is "eighty-one million, fifty-four thousand, five hundred five".