78907689 has 63 divisors (see below), whose sum is σ = 140613357. Its totient is φ = 44130744.

The previous prime is 78907681. The next prime is 78907691. The reversal of 78907689 is 98670987.

The square root of 78907689 is 8883.

It is a perfect power (a square), and thus also a powerful number.

It is a tau number, because it is divible by the number of its divisors (63).

It is not a de Polignac number, because 78907689 - 2³ = 78907681 is a prime.

It is a Smith number, since the sum of its digits (54) coincides with the sum of the digits of its prime factors.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (78907681) by changing a digit.

It is a polite number, since it can be written in 62 ways as a sum of consecutive naturals, for example, 1678864 + ... + 1678910.

Almost surely, 2^78907689 is an apocalyptic number.

78907689 is the 8883-rd square number.

78907689 is the 4442-nd centered octagonal number.

It is an amenable number.

78907689 is a deficient number, since it is larger than the sum of its proper divisors (61705668).

78907689 is an frugal number, since it uses more digits than its factorization.

78907689 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 126 (or 57 counting only the distinct ones).

The product of its (nonzero) digits is 1524096, while the sum is 54.

The cubic root of 78907689 is about 428.9168502352.

The spelling of 78907689 in words is "seventy-eight million, nine hundred seven thousand, six hundred eighty-nine".