20421644322113 has 4 divisors (see below), whose sum is σ = 21125838953940. Its totient is φ = 19717449690288.

The previous prime is 20421644322103. The next prime is 20421644322161. The reversal of 20421644322113 is 31122344612402.

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 16007224815409 + 4414419506704 = 4000903^2 + 2101052^2 .

It is a cyclic number.

It is not a de Polignac number, because 20421644322113 - 2¹² = 20421644318017 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (20421644322103) 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, 352097315870 + ... + 352097315927.

It is an arithmetic number, because the mean of its divisors is an integer number (5281459738485).

Almost surely, 2^{20421644322113} is an apocalyptic number.

It is an amenable number.

20421644322113 is a deficient number, since it is larger than the sum of its proper divisors (704194631827).

20421644322113 is an equidigital number, since it uses as much as digits as its factorization.

20421644322113 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 704194631826.

The product of its (nonzero) digits is 55296, while the sum is 35.

Adding to 20421644322113 its reverse (31122344612402), we get a palindrome (51543988934515).

The spelling of 20421644322113 in words is "twenty trillion, four hundred twenty-one billion, six hundred forty-four million, three hundred twenty-two thousand, one hundred thirteen".