81366867 has 12 divisors (see below), whose sum is σ = 117815880. Its totient is φ = 54112608.

The previous prime is 81366839. The next prime is 81366871. The reversal of 81366867 is 76866318.

It is not a de Polignac number, because 81366867 - 2⁸ = 81366611 is a prime.

It is not an unprimeable number, because it can be changed into a prime (81366067) 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, 7018 + ... + 14559.

It is an arithmetic number, because the mean of its divisors is an integer number (9817990).

Almost surely, 2^81366867 is an apocalyptic number.

81366867 is a deficient number, since it is larger than the sum of its proper divisors (36449013).

81366867 is a wasteful number, since it uses less digits than its factorization.

81366867 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22002 (or 21999 counting only the distinct ones).

The product of its digits is 290304, while the sum is 45.

The square root of 81366867 is about 9020.3584740297. The cubic root of 81366867 is about 433.3271142434.

The spelling of 81366867 in words is "eighty-one million, three hundred sixty-six thousand, eight hundred sixty-seven".