81363867 has 12 divisors (see below), whose sum is σ = 117472824. Its totient is φ = 50069760.

The previous prime is 81363859. The next prime is 81363907. The reversal of 81363867 is 76836318.

It is not a de Polignac number, because 81363867 - 2³ = 81363859 is a prime.

It is not an unprimeable number, because it can be changed into a prime (81363827) 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, 79734 + ... + 80747.

It is an arithmetic number, because the mean of its divisors is an integer number (9789402).

Almost surely, 2^81363867 is an apocalyptic number.

81363867 is a deficient number, since it is larger than the sum of its proper divisors (36108957).

81363867 is a wasteful number, since it uses less digits than its factorization.

81363867 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 160510 (or 160497 counting only the distinct ones).

The product of its digits is 145152, while the sum is 42.

The square root of 81363867 is about 9020.1921819881. The cubic root of 81363867 is about 433.3217885813.

The spelling of 81363867 in words is "eighty-one million, three hundred sixty-three thousand, eight hundred sixty-seven".