78400868 has 48 divisors (see below), whose sum is σ = 172824960. Its totient is φ = 30288384.

The previous prime is 78400867. The next prime is 78400871. The reversal of 78400868 is 86800487.

It is a happy number.

It is a super-2 number, since 2×78400868² = 12293392206306848, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (78400867) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 13148 + ... + 18156.

It is an arithmetic number, because the mean of its divisors is an integer number (3600520).

Almost surely, 2^78400868 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 78400868, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (86412480).

78400868 is an abundant number, since it is smaller than the sum of its proper divisors (94424092).

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

78400868 is a wasteful number, since it uses less digits than its factorization.

78400868 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5076 (or 5074 counting only the distinct ones).

The product of its (nonzero) digits is 86016, while the sum is 41.

The square root of 78400868 is about 8854.4264636395. The cubic root of 78400868 is about 427.9965717255.

The spelling of 78400868 in words is "seventy-eight million, four hundred thousand, eight hundred sixty-eight".