80781 has 4 divisors (see below), whose sum is σ = 107712. Its totient is φ = 53852.

The previous prime is 80779. The next prime is 80783. The reversal of 80781 is 18708.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is an interprime number because it is at equal distance from previous prime (80779) and next prime (80783).

It is a cyclic number.

It is not a de Polignac number, because 80781 - 2¹ = 80779 is a prime.

It is a super-2 number, since 2×80781² = 13051139922, which contains 22 as substring.

It is a D-number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (80783) 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, 13461 + ... + 13466.

It is an arithmetic number, because the mean of its divisors is an integer number (26928).

2⁸⁰⁷⁸¹ is an apocalyptic number.

It is an amenable number.

80781 is a deficient number, since it is larger than the sum of its proper divisors (26931).

80781 is a wasteful number, since it uses less digits than its factorization.

80781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26930.

The product of its (nonzero) digits is 448, while the sum is 24.

The square root of 80781 is about 284.2199852227. The cubic root of 80781 is about 43.2284577584.

It can be divided in two parts, 807 and 81, that added together give a palindrome (888).

The spelling of 80781 in words is "eighty thousand, seven hundred eighty-one".