78161 has 4 divisors (see below), whose sum is σ = 79872. Its totient is φ = 76452.

The previous prime is 78157. The next prime is 78163. The reversal of 78161 is 16187.

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 a cyclic number.

It is not a de Polignac number, because 78161 - 2² = 78157 is a prime.

It is a super-2 number, since 2×78161² = 12218283842, which contains 22 as substring.

It is an alternating number because its digits alternate between odd and even.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (78163) 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, 785 + ... + 878.

It is an arithmetic number, because the mean of its divisors is an integer number (19968).

2⁷⁸¹⁶¹ is an apocalyptic number.

It is an amenable number.

78161 is a deficient number, since it is larger than the sum of its proper divisors (1711).

78161 is a wasteful number, since it uses less digits than its factorization.

78161 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1710.

The product of its digits is 336, while the sum is 23.

The square root of 78161 is about 279.5728885282. The cubic root of 78161 is about 42.7559639662.

The spelling of 78161 in words is "seventy-eight thousand, one hundred sixty-one".