78021600 has 288 divisors, whose sum is σ = 281232000. Its totient is φ = 18708480.

The previous prime is 78021569. The next prime is 78021607. The reversal of 78021600 is 612087.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78021607) 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 47 ways as a sum of consecutive naturals, for example, 1322371 + ... + 1322429.

It is an arithmetic number, because the mean of its divisors is an integer number (976500).

Almost surely, 2^78021600 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 78021600, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (140616000).

78021600 is an abundant number, since it is smaller than the sum of its proper divisors (203210400).

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

78021600 is a wasteful number, since it uses less digits than its factorization.

78021600 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 130 (or 117 counting only the distinct ones).

The product of its (nonzero) digits is 672, while the sum is 24.

The square root of 78021600 is about 8832.9836408770. The cubic root of 78021600 is about 427.3053044560.

Adding to 78021600 its reverse (612087), we get a palindrome (78633687).

The spelling of 78021600 in words is "seventy-eight million, twenty-one thousand, six hundred".