81526555 has 8 divisors (see below), whose sum is σ = 106725744. Its totient is φ = 59292000.

The previous prime is 81526553. The next prime is 81526567. The reversal of 81526555 is 55562518.

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

It is not a de Polignac number, because 81526555 - 2¹ = 81526553 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81526553) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 741096 + ... + 741205.

It is an arithmetic number, because the mean of its divisors is an integer number (13340718).

Almost surely, 2^81526555 is an apocalyptic number.

81526555 is a deficient number, since it is larger than the sum of its proper divisors (25199189).

81526555 is a wasteful number, since it uses less digits than its factorization.

81526555 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1482317.

The product of its digits is 60000, while the sum is 37.

The square root of 81526555 is about 9029.2056682745. The cubic root of 81526555 is about 433.6104069563.

The spelling of 81526555 in words is "eighty-one million, five hundred twenty-six thousand, five hundred fifty-five".