78438564 has 48 divisors (see below), whose sum is σ = 204624000. Its totient is φ = 25983648.

The previous prime is 78438559. The next prime is 78438583. The reversal of 78438564 is 46583487.

78438564 is a `hidden beast` number, since 7 + 84 + 3 + 8 + 564 = 666.

It is a zygodrome in base 6.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 15862 + ... + 20210.

It is an arithmetic number, because the mean of its divisors is an integer number (4263000).

Almost surely, 2^78438564 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 78438564, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (102312000).

78438564 is an abundant number, since it is smaller than the sum of its proper divisors (126185436).

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

78438564 is a wasteful number, since it uses less digits than its factorization.

78438564 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4529 (or 4521 counting only the distinct ones).

The product of its digits is 645120, while the sum is 45.

The square root of 78438564 is about 8856.5548606668. The cubic root of 78438564 is about 428.0651558884.

The spelling of 78438564 in words is "seventy-eight million, four hundred thirty-eight thousand, five hundred sixty-four".