20550507777 has 24 divisors (see below), whose sum is σ = 30576168168. Its totient is φ = 13292294400.

The previous prime is 20550507767. The next prime is 20550507793. The reversal of 20550507777 is 77770505502.

20550507777 is a `hidden beast` number, since 2 + 0 + 5 + 505 + 0 + 77 + 77 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 3466972161 + 17083535616 = 58881^2 + 130704^2 .

It is not a de Polignac number, because 20550507777 - 2¹² = 20550503681 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20550507727) 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, 87058 + ... + 220635.

It is an arithmetic number, because the mean of its divisors is an integer number (1274007007).

Almost surely, 2^20550507777 is an apocalyptic number.

It is an amenable number.

20550507777 is a deficient number, since it is larger than the sum of its proper divisors (10025660391).

20550507777 is a wasteful number, since it uses less digits than its factorization.

20550507777 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 307921 (or 307918 counting only the distinct ones).

The product of its (nonzero) digits is 600250, while the sum is 45.

The spelling of 20550507777 in words is "twenty billion, five hundred fifty million, five hundred seven thousand, seven hundred seventy-seven".