78189408 has 192 divisors, whose sum is σ = 262483200. Its totient is φ = 22394880.

The previous prime is 78189407. The next prime is 78189421. The reversal of 78189408 is 80498187.

It is a super-2 number, since 2×78189408² = 12227167046780928, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78189401) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 180360 + ... + 180792.

It is an arithmetic number, because the mean of its divisors is an integer number (1367100).

Almost surely, 2^78189408 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 78189408, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (131241600).

78189408 is an abundant number, since it is smaller than the sum of its proper divisors (184293792).

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

78189408 is a wasteful number, since it uses less digits than its factorization.

78189408 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 482 (or 468 counting only the distinct ones).

The product of its (nonzero) digits is 129024, while the sum is 45.

The square root of 78189408 is about 8842.4774808874. The cubic root of 78189408 is about 427.6114329395.

The spelling of 78189408 in words is "seventy-eight million, one hundred eighty-nine thousand, four hundred eight".