78408 has 60 divisors (see below), whose sum is σ = 241395. Its totient is φ = 23760.

The previous prime is 78401. The next prime is 78427. The reversal of 78408 is 80487.

It is a happy number.

It is a powerful number, because all its prime factors have an exponent greater than 1 and also an Achilles number because it is not a perfect power.

It can be written as a sum of positive squares in only one way, i.e., 39204 + 39204 = 198^2 + 198^2 .

It is an ABA number since it can be written as A⋅B^A, here for A=2, B=198.

It is a super-2 number, since 2×78408² = 12295628928, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a nialpdrome in base 7.

It is a zygodrome in base 7.

It is not an unprimeable number, because it can be changed into a prime (78401) by changing a digit.

78408 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 14 ways as a sum of consecutive naturals, for example, 7123 + ... + 7133.

2⁷⁸⁴⁰⁸ is an apocalyptic number.

78408 is the 162-nd octagonal number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 78408

78408 is an abundant number, since it is smaller than the sum of its proper divisors (162987).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

78408 is a wasteful number, since it uses less digits than its factorization.

78408 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40 (or 16 counting only the distinct ones).

The product of its (nonzero) digits is 1792, while the sum is 27.

The square root of 78408 is about 280.0142853499. The cubic root of 78408 is about 42.8009549384.

Adding to 78408 its product of nonzero digits (1792), we get a triangular number (80200 = T₄₀₀).

The spelling of 78408 in words is "seventy-eight thousand, four hundred eight".