78788787 has 48 divisors (see below), whose sum is σ = 133706496. Its totient is φ = 40392000.

The previous prime is 78788767. The next prime is 78788789.

78788787 is nontrivially palindromic in base 10.

It is not a de Polignac number, because 78788787 - 2¹² = 78784691 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 78788787.

It is not an unprimeable number, because it can be changed into a prime (78788789) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 256488 + ... + 256794.

It is an arithmetic number, because the mean of its divisors is an integer number (2785552).

Almost surely, 2^78788787 is an apocalyptic number.

78788787 is a gapful number since it is divisible by the number (77) formed by its first and last digit.

78788787 is a deficient number, since it is larger than the sum of its proper divisors (54917709).

78788787 is a wasteful number, since it uses less digits than its factorization.

78788787 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 440 (or 429 counting only the distinct ones).

The product of its digits is 9834496, while the sum is 60.

The square root of 78788787 is about 8876.3048054920. The cubic root of 78788787 is about 428.7013042413.

The spelling of 78788787 in words is "seventy-eight million, seven hundred eighty-eight thousand, seven hundred eighty-seven".