81169811 has 8 divisors (see below), whose sum is σ = 86678400. Its totient is φ = 75841920.

The previous prime is 81169789. The next prime is 81169813. The reversal of 81169811 is 11896118.

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

It is a cyclic number.

It is not a de Polignac number, because 81169811 - 2¹⁸ = 80907667 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81169813) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 44246 + ... + 46043.

It is an arithmetic number, because the mean of its divisors is an integer number (10834800).

Almost surely, 2^81169811 is an apocalyptic number.

81169811 is a deficient number, since it is larger than the sum of its proper divisors (5508589).

81169811 is a wasteful number, since it uses less digits than its factorization.

81169811 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 90349.

The product of its digits is 3456, while the sum is 35.

The square root of 81169811 is about 9009.4290052145. The cubic root of 81169811 is about 432.9770178764.

The spelling of 81169811 in words is "eighty-one million, one hundred sixty-nine thousand, eight hundred eleven".