81068669 has 6 divisors (see below), whose sum is σ = 89108670. Its totient is φ = 73698680.

The previous prime is 81068653. The next prime is 81068683. The reversal of 81068669 is 96686018.

It can be written as a sum of positive squares in only one way, i.e., 80766169 + 302500 = 8987^2 + 550^2 .

It is not a de Polignac number, because 81068669 - 2⁴ = 81068653 is a prime.

It is a super-2 number, since 2×81068669² = 13144258186863122, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81068609) 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 5 ways as a sum of consecutive naturals, for example, 334874 + ... + 335115.

It is an arithmetic number, because the mean of its divisors is an integer number (14851445).

Almost surely, 2^81068669 is an apocalyptic number.

It is an amenable number.

81068669 is a deficient number, since it is larger than the sum of its proper divisors (8040001).

81068669 is a wasteful number, since it uses less digits than its factorization.

81068669 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 670011 (or 670000 counting only the distinct ones).

The product of its (nonzero) digits is 124416, while the sum is 44.

The square root of 81068669 is about 9003.8141362425. The cubic root of 81068669 is about 432.7971054897.

The spelling of 81068669 in words is "eighty-one million, sixty-eight thousand, six hundred sixty-nine".