81148136 has 8 divisors (see below), whose sum is σ = 152152770. Its totient is φ = 40574064.

The previous prime is 81148127. The next prime is 81148159. The reversal of 81148136 is 63184118.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 79103236 + 2044900 = 8894^2 + 1430^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is an unprimeable number.

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, 5071751 + ... + 5071766.

Almost surely, 2^81148136 is an apocalyptic number.

It is an amenable number.

81148136 is a deficient number, since it is larger than the sum of its proper divisors (71004634).

81148136 is a wasteful number, since it uses less digits than its factorization.

81148136 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10143523 (or 10143519 counting only the distinct ones).

The product of its digits is 4608, while the sum is 32.

The square root of 81148136 is about 9008.2260184789. The cubic root of 81148136 is about 432.9384747604.

The spelling of 81148136 in words is "eighty-one million, one hundred forty-eight thousand, one hundred thirty-six".