78981 has 8 divisors (see below), whose sum is σ = 120384. Its totient is φ = 45120.

The previous prime is 78979. The next prime is 78989. The reversal of 78981 is 18987.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 78981 - 2¹ = 78979 is a prime.

It is a super-2 number, since 2×78981² = 12475996722, which contains 22 as substring.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78989) 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 7 ways as a sum of consecutive naturals, for example, 1860 + ... + 1901.

It is an arithmetic number, because the mean of its divisors is an integer number (15048).

2⁷⁸⁹⁸¹ is an apocalyptic number.

It is an amenable number.

78981 is a deficient number, since it is larger than the sum of its proper divisors (41403).

78981 is a wasteful number, since it uses less digits than its factorization.

78981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3771.

The product of its digits is 4032, while the sum is 33.

The square root of 78981 is about 281.0355849354. The cubic root of 78981 is about 42.9049640802.

The spelling of 78981 in words is "seventy-eight thousand, nine hundred eighty-one".