7781688345 has 16 divisors (see below), whose sum is σ = 12453782400. Its totient is φ = 4149206784.

The previous prime is 7781688289. The next prime is 7781688353. The reversal of 7781688345 is 5438861877.

It is not a de Polignac number, because 7781688345 - 2⁶ = 7781688281 is a prime.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 556 + ... + 124754.

It is an arithmetic number, because the mean of its divisors is an integer number (778361400).

Almost surely, 2^7781688345 is an apocalyptic number.

It is an amenable number.

7781688345 is a deficient number, since it is larger than the sum of its proper divisors (4672094055).

7781688345 is a wasteful number, since it uses less digits than its factorization.

7781688345 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 128384.

The product of its digits is 9031680, while the sum is 57.

The square root of 7781688345 is about 88213.8784149070. The cubic root of 7781688345 is about 1981.6393206139.

The spelling of 7781688345 in words is "seven billion, seven hundred eighty-one million, six hundred eighty-eight thousand, three hundred forty-five".