21003113101 has 4 divisors (see below), whose sum is σ = 21078936892. Its totient is φ = 20927289312.

The previous prime is 21003113081. The next prime is 21003113129. The reversal of 21003113101 is 10131130012.

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 14623097476 + 6380015625 = 120926^2 + 79875^2 .

It is a cyclic number.

It is not a de Polignac number, because 21003113101 - 2¹¹ = 21003111053 is a prime.

It is a super-2 number, since 2×21003113101² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21003114101) 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, 37911480 + ... + 37912033.

It is an arithmetic number, because the mean of its divisors is an integer number (5269734223).

Almost surely, 2^21003113101 is an apocalyptic number.

It is an amenable number.

21003113101 is a deficient number, since it is larger than the sum of its proper divisors (75823791).

21003113101 is an equidigital number, since it uses as much as digits as its factorization.

21003113101 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 75823790.

The product of its (nonzero) digits is 18, while the sum is 13.

Adding to 21003113101 its reverse (10131130012), we get a palindrome (31134243113).

The spelling of 21003113101 in words is "twenty-one billion, three million, one hundred thirteen thousand, one hundred one".