78723400 has 144 divisors (see below), whose sum is σ = 221051700. Its totient is φ = 25966080.

The previous prime is 78723377. The next prime is 78723401. The reversal of 78723400 is 432787.

It can be written as a sum of positive squares in 6 ways, for example, as 16597476 + 62125924 = 4074^2 + 7882^2 .

It is not an unprimeable number, because it can be changed into a prime (78723401) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 284062 + ... + 284338.

Almost surely, 2^78723400 is an apocalyptic number.

78723400 is a gapful number since it is divisible by the number (70) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 78723400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (110525850).

78723400 is an abundant number, since it is smaller than the sum of its proper divisors (142328300).

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

78723400 is a wasteful number, since it uses less digits than its factorization.

78723400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 336 (or 320 counting only the distinct ones).

The product of its (nonzero) digits is 9408, while the sum is 31.

The square root of 78723400 is about 8872.6208078560. The cubic root of 78723400 is about 428.5826780116.

The spelling of 78723400 in words is "seventy-eight million, seven hundred twenty-three thousand, four hundred".