78971 has 4 divisors (see below), whose sum is σ = 79632. Its totient is φ = 78312.

The previous prime is 78941. The next prime is 78977. The reversal of 78971 is 17987.

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 a de Polignac number, because none of the positive numbers 2^k-78971 is a prime.

It is a Duffinian number.

It is a plaindrome in base 16.

It is not an unprimeable number, because it can be changed into a prime (78977) 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, 95 + ... + 408.

It is an arithmetic number, because the mean of its divisors is an integer number (19908).

2⁷⁸⁹⁷¹ is an apocalyptic number.

78971 is a deficient number, since it is larger than the sum of its proper divisors (661).

78971 is a wasteful number, since it uses less digits than its factorization.

78971 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 660.

The product of its digits is 3528, while the sum is 32.

The square root of 78971 is about 281.0177930310. The cubic root of 78971 is about 42.9031532322.

Adding to 78971 its sum of digits (32), we get a triangular number (79003 = T₃₉₇).

The spelling of 78971 in words is "seventy-eight thousand, nine hundred seventy-one".