81377927 has 4 divisors (see below), whose sum is σ = 81433296. Its totient is φ = 81322560.

The previous prime is 81377909. The next prime is 81377953. The reversal of 81377927 is 72977318.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 81377927 - 2¹⁴ = 81361543 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81377987) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 25418 + ... + 28439.

It is an arithmetic number, because the mean of its divisors is an integer number (20358324).

Almost surely, 2^81377927 is an apocalyptic number.

81377927 is a deficient number, since it is larger than the sum of its proper divisors (55369).

81377927 is a wasteful number, since it uses less digits than its factorization.

81377927 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 55368.

The product of its digits is 148176, while the sum is 44.

The square root of 81377927 is about 9020.9715108740. The cubic root of 81377927 is about 433.3467470535.

The spelling of 81377927 in words is "eighty-one million, three hundred seventy-seven thousand, nine hundred twenty-seven".