81552738 has 8 divisors (see below), whose sum is σ = 163105488. Its totient is φ = 27184244.

The previous prime is 81552707. The next prime is 81552739. The reversal of 81552738 is 83725518.

It is a sphenic number, since it is the product of 3 distinct primes.

81552738 is an admirable number.

It is a junction number, because it is equal to n+sod(n) for n = 81552696 and 81552705.

It is not an unprimeable number, because it can be changed into a prime (81552739) 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 in 3 ways as a sum of consecutive naturals, for example, 6796056 + ... + 6796067.

It is an arithmetic number, because the mean of its divisors is an integer number (20388186).

Almost surely, 2^81552738 is an apocalyptic number.

81552738 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

81552738 is a wasteful number, since it uses less digits than its factorization.

81552738 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13592128.

The product of its digits is 67200, while the sum is 39.

The square root of 81552738 is about 9030.6554579388. The cubic root of 81552738 is about 433.6568213061.

The spelling of 81552738 in words is "eighty-one million, five hundred fifty-two thousand, seven hundred thirty-eight".