81078068 has 6 divisors (see below), whose sum is σ = 141886626. Its totient is φ = 40539032.

The previous prime is 81078061. The next prime is 81078071. The reversal of 81078068 is 86087018.

It can be written as a sum of positive squares in only one way, i.e., 75134224 + 5943844 = 8668^2 + 2438^2 .

It is a super-2 number, since 2×81078068² = 13147306221225248, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81078061) 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, 10134755 + ... + 10134762.

It is an arithmetic number, because the mean of its divisors is an integer number (23647771).

Almost surely, 2^81078068 is an apocalyptic number.

It is an amenable number.

81078068 is a deficient number, since it is larger than the sum of its proper divisors (60808558).

81078068 is a wasteful number, since it uses less digits than its factorization.

81078068 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20269521 (or 20269519 counting only the distinct ones).

The product of its (nonzero) digits is 21504, while the sum is 38.

The square root of 81078068 is about 9004.3360665848. The cubic root of 81078068 is about 432.8138308282.

The spelling of 81078068 in words is "eighty-one million, seventy-eight thousand, sixty-eight".