20013100021 has 4 divisors (see below), whose sum is σ = 20254221792. Its totient is φ = 19771978252.

The previous prime is 20013099973. The next prime is 20013100039. The reversal of 20013100021 is 12000131002.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 20013100021 - 2²³ = 20004711413 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20013099980 and 20013100007.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20013106021) 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, 120560761 + ... + 120560926.

It is an arithmetic number, because the mean of its divisors is an integer number (5063555448).

Almost surely, 2^20013100021 is an apocalyptic number.

It is an amenable number.

20013100021 is a deficient number, since it is larger than the sum of its proper divisors (241121771).

20013100021 is an equidigital number, since it uses as much as digits as its factorization.

20013100021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 241121770.

The product of its (nonzero) digits is 12, while the sum is 10.

Adding to 20013100021 its reverse (12000131002), we get a palindrome (32013231023).

The spelling of 20013100021 in words is "twenty billion, thirteen million, one hundred thousand, twenty-one".