81130133 has 32 divisors (see below), whose sum is σ = 101760000. Its totient is φ = 64456560.

The previous prime is 81130129. The next prime is 81130163. The reversal of 81130133 is 33103118.

It is a happy number.

It is not a de Polignac number, because 81130133 - 2² = 81130129 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81130163) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 384398 + ... + 384608.

It is an arithmetic number, because the mean of its divisors is an integer number (3180000).

Almost surely, 2^81130133 is an apocalyptic number.

It is an amenable number.

81130133 is a deficient number, since it is larger than the sum of its proper divisors (20629867).

81130133 is a wasteful number, since it uses less digits than its factorization.

81130133 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 310 (or 296 counting only the distinct ones).

The product of its (nonzero) digits is 216, while the sum is 20.

The square root of 81130133 is about 9007.2267097037. The cubic root of 81130133 is about 432.9064560836.

The spelling of 81130133 in words is "eighty-one million, one hundred thirty thousand, one hundred thirty-three".