81081004 has 6 divisors (see below), whose sum is σ = 141891764. Its totient is φ = 40540500.

The previous prime is 81081001. The next prime is 81081019. The reversal of 81081004 is 40018018.

It is not an unprimeable number, because it can be changed into a prime (81081001) 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 as a sum of consecutive naturals, namely, 10135122 + ... + 10135129.

Almost surely, 2^81081004 is an apocalyptic number.

It is an amenable number.

81081004 is a deficient number, since it is larger than the sum of its proper divisors (60810760).

81081004 is a wasteful number, since it uses less digits than its factorization.

81081004 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20270255 (or 20270253 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 22.

The square root of 81081004 is about 9004.4990976733. The cubic root of 81081004 is about 432.8190551184.

The spelling of 81081004 in words is "eighty-one million, eighty-one thousand, four".