77787897 has 16 divisors (see below), whose sum is σ = 116797440. Its totient is φ = 45622800.

The previous prime is 77787887. The next prime is 77787907. The reversal of 77787897 is 79878777.

It is an interprime number because it is at equal distance from previous prime (77787887) and next prime (77787907).

It is not a de Polignac number, because 77787897 - 2¹⁰ = 77786873 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 77787897.

It is not an unprimeable number, because it can be changed into a prime (77787847) 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, 36997 + ... + 39042.

It is an arithmetic number, because the mean of its divisors is an integer number (7299840).

Almost surely, 2^77787897 is an apocalyptic number.

It is an amenable number.

77787897 is a deficient number, since it is larger than the sum of its proper divisors (39009543).

77787897 is a wasteful number, since it uses less digits than its factorization.

77787897 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 76084.

The product of its digits is 9680832, while the sum is 60.

The square root of 77787897 is about 8819.7447241970. The cubic root of 77787897 is about 426.8782329528.

The spelling of 77787897 in words is "seventy-seven million, seven hundred eighty-seven thousand, eight hundred ninety-seven".