7779428505 has 24 divisors (see below), whose sum is σ = 13491970440. Its totient is φ = 4146681600.

The previous prime is 7779428479. The next prime is 7779428507. The reversal of 7779428505 is 5058249777.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 122478489 + 7656950016 = 11067^2 + 87504^2 .

It is not a de Polignac number, because 7779428505 - 2⁸ = 7779428249 is a prime.

It is not an unprimeable number, because it can be changed into a prime (7779428507) by changing a digit.

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 23 ways as a sum of consecutive naturals, for example, 33051 + ... + 129039.

It is an arithmetic number, because the mean of its divisors is an integer number (562165435).

Almost surely, 2^7779428505 is an apocalyptic number.

It is an amenable number.

7779428505 is a deficient number, since it is larger than the sum of its proper divisors (5712541935).

7779428505 is a wasteful number, since it uses less digits than its factorization.

7779428505 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 97801 (or 97798 counting only the distinct ones).

The product of its (nonzero) digits is 4939200, while the sum is 54.

The square root of 7779428505 is about 88201.0686159754. The cubic root of 7779428505 is about 1981.4474761551.

The spelling of 7779428505 in words is "seven billion, seven hundred seventy-nine million, four hundred twenty-eight thousand, five hundred five".