78988987 has 16 divisors (see below), whose sum is σ = 104274432. Its totient is φ = 57928320.

The previous prime is 78988937. The next prime is 78988997.

78988987 is nontrivially palindromic in base 10.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-78988987 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (78988927) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 28863 + ... + 31480.

It is an arithmetic number, because the mean of its divisors is an integer number (6517152).

Almost surely, 2^78988987 is an apocalyptic number.

78988987 is a gapful number since it is divisible by the number (77) formed by its first and last digit.

78988987 is a deficient number, since it is larger than the sum of its proper divisors (25285445).

78988987 is a wasteful number, since it uses less digits than its factorization.

78988987 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 60378.

The product of its digits is 16257024, while the sum is 64.

The square root of 78988987 is about 8887.5748660700. The cubic root of 78988987 is about 429.0641029466.

The spelling of 78988987 in words is "seventy-eight million, nine hundred eighty-eight thousand, nine hundred eighty-seven".