78780000 has 240 divisors, whose sum is σ = 281047536. Its totient is φ = 19200000.

The previous prime is 78779977. The next prime is 78780001. The reversal of 78780000 is 8787.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (240).

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a self number, because there is not a number n which added to its sum of digits gives 78780000.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78780001) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 779950 + ... + 780050.

Almost surely, 2^78780000 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 78780000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (140523768).

78780000 is an abundant number, since it is smaller than the sum of its proper divisors (202267536).

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

78780000 is a wasteful number, since it uses less digits than its factorization.

78780000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 147 (or 124 counting only the distinct ones).

The product of its (nonzero) digits is 3136, while the sum is 30.

The square root of 78780000 is about 8875.8098222078. The cubic root of 78780000 is about 428.6853665317.

Adding to 78780000 its reverse (8787), we get a palindrome (78788787).

It can be divided in two parts, 78 and 780000, that multiplied together give a square (60840000 = 7800²).

The spelling of 78780000 in words is "seventy-eight million, seven hundred eighty thousand".