81667528 has 8 divisors (see below), whose sum is σ = 153126630. Its totient is φ = 40833760.

The previous prime is 81667519. The next prime is 81667543. The reversal of 81667528 is 82576618.

It can be written as a sum of positive squares in only one way, i.e., 48972004 + 32695524 = 6998^2 + 5718^2 .

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, 5104213 + ... + 5104228.

Almost surely, 2^81667528 is an apocalyptic number.

It is an amenable number.

81667528 is a deficient number, since it is larger than the sum of its proper divisors (71459102).

81667528 is a wasteful number, since it uses less digits than its factorization.

81667528 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10208447 (or 10208443 counting only the distinct ones).

The product of its digits is 161280, while the sum is 43.

The square root of 81667528 is about 9037.0087971629. The cubic root of 81667528 is about 433.8601912570.

The spelling of 81667528 in words is "eighty-one million, six hundred sixty-seven thousand, five hundred twenty-eight".