78774647787 has 72 divisors (see below), whose sum is σ = 133795469808. Its totient is φ = 44469596160.

The previous prime is 78774647717. The next prime is 78774647797.

It is a happy number.

78774647787 is a `hidden beast` number, since 7 + 8 + 7 + 74 + 6 + 477 + 87 = 666.

78774647787 is nontrivially palindromic in base 10.

It is not a de Polignac number, because 78774647787 - 2⁸ = 78774647531 is a prime.

It is not an unprimeable number, because it can be changed into a prime (78774647717) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 1773828 + ... + 1817694.

It is an arithmetic number, because the mean of its divisors is an integer number (1858270414).

Almost surely, 2^78774647787 is an apocalyptic number.

78774647787 is a deficient number, since it is larger than the sum of its proper divisors (55020822021).

78774647787 is a wasteful number, since it uses less digits than its factorization.

78774647787 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 44009 (or 43995 counting only the distinct ones).

The product of its digits is 722835456, while the sum is 72.

The spelling of 78774647787 in words is "seventy-eight billion, seven hundred seventy-four million, six hundred forty-seven thousand, seven hundred eighty-seven".