20863449853 has 4 divisors (see below), whose sum is σ = 20863967740. Its totient is φ = 20862931968.

The previous prime is 20863449839. The next prime is 20863449863. The reversal of 20863449853 is 35894436802.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 5950888164 + 14912561689 = 77142^2 + 122117^2 .

It is a cyclic number.

It is not a de Polignac number, because 20863449853 - 2⁵ = 20863449821 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20863449853.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20863449863) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 192900 + ... + 280957.

It is an arithmetic number, because the mean of its divisors is an integer number (5215991935).

Almost surely, 2^20863449853 is an apocalyptic number.

It is an amenable number.

20863449853 is a deficient number, since it is larger than the sum of its proper divisors (517887).

20863449853 is an equidigital number, since it uses as much as digits as its factorization.

20863449853 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 517886.

The product of its (nonzero) digits is 4976640, while the sum is 52.

The spelling of 20863449853 in words is "twenty billion, eight hundred sixty-three million, four hundred forty-nine thousand, eight hundred fifty-three".