20855878663 has 2 divisors, whose sum is σ = 20855878664. Its totient is φ = 20855878662.

The previous prime is 20855878627. The next prime is 20855878679. The reversal of 20855878663 is 36687855802.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 20855878663 - 2²¹ = 20853781511 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20855878598 and 20855878607.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20855828663) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10427939331 + 10427939332.

It is an arithmetic number, because the mean of its divisors is an integer number (10427939332).

Almost surely, 2^20855878663 is an apocalyptic number.

20855878663 is a deficient number, since it is larger than the sum of its proper divisors (1).

20855878663 is an equidigital number, since it uses as much as digits as its factorization.

20855878663 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 19353600, while the sum is 58.

The spelling of 20855878663 in words is "twenty billion, eight hundred fifty-five million, eight hundred seventy-eight thousand, six hundred sixty-three".