81004995 has 32 divisors (see below), whose sum is σ = 144801600. Its totient is φ = 42964992.

The previous prime is 81004993. The next prime is 81005009. The reversal of 81004995 is 59940018.

It is not a de Polignac number, because 81004995 - 2¹ = 81004993 is a prime.

It is not an unprimeable number, because it can be changed into a prime (81004993) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 24501 + ... + 27609.

It is an arithmetic number, because the mean of its divisors is an integer number (4525050).

Almost surely, 2^81004995 is an apocalyptic number.

81004995 is a deficient number, since it is larger than the sum of its proper divisors (63796605).

81004995 is a wasteful number, since it uses less digits than its factorization.

81004995 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3316 (or 3310 counting only the distinct ones).

The product of its (nonzero) digits is 12960, while the sum is 36.

The square root of 81004995 is about 9000.2774957220. The cubic root of 81004995 is about 432.6837647818.

The spelling of 81004995 in words is "eighty-one million, four thousand, nine hundred ninety-five".