20853312642 has 54 divisors (see below), whose sum is σ = 45769769019. Its totient is φ = 6861859200.

The previous prime is 20853312619. The next prime is 20853312647. The reversal of 20853312642 is 24621335802.

20853312642 is a `hidden beast` number, since 2 + 0 + 8 + 5 + 3 + 3 + 1 + 2 + 642 = 666.

It can be written as a sum of positive squares in 5 ways, for example, as 17090594361 + 3762718281 = 130731^2 + 61341^2 .

It is an ABA number since it can be written as A⋅B^A, here for A=2, B=102111.

It is a junction number, because it is equal to n+sod(n) for n = 20853312597 and 20853312606.

It is not an unprimeable number, because it can be changed into a prime (20853312647) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 61879098 + ... + 61879434.

Almost surely, 2^20853312642 is an apocalyptic number.

20853312642 is an abundant number, since it is smaller than the sum of its proper divisors (24916456377).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20853312642 is an equidigital number, since it uses as much as digits as its factorization.

20853312642 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 884 (or 443 counting only the distinct ones).

The product of its (nonzero) digits is 69120, while the sum is 36.

The spelling of 20853312642 in words is "twenty billion, eight hundred fifty-three million, three hundred twelve thousand, six hundred forty-two".