81206667 has 12 divisors (see below), whose sum is σ = 117382720. Its totient is φ = 54098928.

The previous prime is 81206663. The next prime is 81206669. The reversal of 81206667 is 76660218.

It is a happy number.

It is not a de Polignac number, because 81206667 - 2² = 81206663 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81206663) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 16038 + ... + 20484.

Almost surely, 2^81206667 is an apocalyptic number.

81206667 is a deficient number, since it is larger than the sum of its proper divisors (36176053).

81206667 is a wasteful number, since it uses less digits than its factorization.

81206667 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6482 (or 6479 counting only the distinct ones).

The product of its (nonzero) digits is 24192, while the sum is 36.

The square root of 81206667 is about 9011.4741857257. The cubic root of 81206667 is about 433.0425405386.

The spelling of 81206667 in words is "eighty-one million, two hundred six thousand, six hundred sixty-seven".