20779655563 has 16 divisors (see below), whose sum is σ = 21704304960. Its totient is φ = 19869696000.

The previous prime is 20779655549. The next prime is 20779655573. The reversal of 20779655563 is 36555697702.

It is a cyclic number.

It is not a de Polignac number, because 20779655563 - 2²¹ = 20777558411 is a prime.

It is a super-3 number, since 3×20779655563³ (a number of 32 digits) contains 333 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20779655503) 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, 1468683 + ... + 1482763.

It is an arithmetic number, because the mean of its divisors is an integer number (1356519060).

Almost surely, 2^20779655563 is an apocalyptic number.

20779655563 is a deficient number, since it is larger than the sum of its proper divisors (924649397).

20779655563 is a wasteful number, since it uses less digits than its factorization.

20779655563 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14598.

The product of its (nonzero) digits is 11907000, while the sum is 55.

The spelling of 20779655563 in words is "twenty billion, seven hundred seventy-nine million, six hundred fifty-five thousand, five hundred sixty-three".