86978 has 8 divisors (see below), whose sum is σ = 131772. Its totient is φ = 43056.

The previous prime is 86969. The next prime is 86981. The reversal of 86978 is 87968.

It can be written as a sum of positive squares in 2 ways, for example, as 80089 + 6889 = 283^2 + 83^2 .

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

It is a plaindrome in base 14.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 176 + ... + 452.

2⁸⁶⁹⁷⁸ is an apocalyptic number.

86978 is a deficient number, since it is larger than the sum of its proper divisors (44794).

86978 is a wasteful number, since it uses less digits than its factorization.

86978 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 436.

The product of its digits is 24192, while the sum is 38.

The square root of 86978 is about 294.9203282244. The cubic root of 86978 is about 44.3067409194.

Subtracting 86978 from its reverse (87968), we obtain a triangular number (990 = T₄₄).

The spelling of 86978 in words is "eighty-six thousand, nine hundred seventy-eight".