21100030213 has 4 divisors (see below), whose sum is σ = 21100356288. Its totient is φ = 21099704140.

The previous prime is 21100030207. The next prime is 21100030243. The reversal of 21100030213 is 31203000112.

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 a de Polignac number, because none of the positive numbers 2^k-21100030213 is a prime.

It is a super-2 number, since 2×21100030213² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21100030193 and 21100030202.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21100030243) 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, 29533 + ... + 207538.

It is an arithmetic number, because the mean of its divisors is an integer number (5275089072).

Almost surely, 2^21100030213 is an apocalyptic number.

It is an amenable number.

21100030213 is a deficient number, since it is larger than the sum of its proper divisors (326075).

21100030213 is an equidigital number, since it uses as much as digits as its factorization.

21100030213 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 326074.

The product of its (nonzero) digits is 36, while the sum is 13.

Adding to 21100030213 its reverse (31203000112), we get a palindrome (52303030325).

The spelling of 21100030213 in words is "twenty-one billion, one hundred million, thirty thousand, two hundred thirteen".