7728578274649 has 16 divisors (see below), whose sum is σ = 7862917727808. Its totient is φ = 7594806428352.

The previous prime is 7728578274619. The next prime is 7728578274653. The reversal of 7728578274649 is 9464728758277.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-7728578274649 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (7728578274619) 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, 118771807 + ... + 118836859.

It is an arithmetic number, because the mean of its divisors is an integer number (491432357988).

Almost surely, 2^{7728578274649} is an apocalyptic number.

It is an amenable number.

7728578274649 is a deficient number, since it is larger than the sum of its proper divisors (134339453159).

7728578274649 is a wasteful number, since it uses less digits than its factorization.

7728578274649 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 69384.

The product of its digits is 2655313920, while the sum is 76.

The spelling of 7728578274649 in words is "seven trillion, seven hundred twenty-eight billion, five hundred seventy-eight million, two hundred seventy-four thousand, six hundred forty-nine".