77971 has 4 divisors (see below), whose sum is σ = 78832. Its totient is φ = 77112.

The previous prime is 77969. The next prime is 77977. The reversal of 77971 is 17977.

77971 is nontrivially palindromic in base 15.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 77971 - 2¹ = 77969 is a prime.

It is a Duffinian number.

77971 is an undulating number in base 15.

It is not an unprimeable number, because it can be changed into a prime (77977) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 276 + ... + 481.

It is an arithmetic number, because the mean of its divisors is an integer number (19708).

2⁷⁷⁹⁷¹ is an apocalyptic number.

77971 is a deficient number, since it is larger than the sum of its proper divisors (861).

77971 is a wasteful number, since it uses less digits than its factorization.

77971 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 860.

The product of its digits is 3087, while the sum is 31.

The square root of 77971 is about 279.2328777204. The cubic root of 77971 is about 42.7212909853.

The spelling of 77971 in words is "seventy-seven thousand, nine hundred seventy-one".