21211021101 has 4 divisors (see below), whose sum is σ = 28281361472. Its totient is φ = 14140680732.

The previous prime is 21211021081. The next prime is 21211021121. The reversal of 21211021101 is 10112011212.

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 an interprime number because it is at equal distance from previous prime (21211021081) and next prime (21211021121).

It is not a de Polignac number, because 21211021101 - 2¹⁸ = 21210758957 is a prime.

It is a super-2 number, since 2×21211021101² (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 (21211021121) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3535170181 + ... + 3535170186.

It is an arithmetic number, because the mean of its divisors is an integer number (7070340368).

Almost surely, 2^21211021101 is an apocalyptic number.

It is an amenable number.

21211021101 is a deficient number, since it is larger than the sum of its proper divisors (7070340371).

21211021101 is an equidigital number, since it uses as much as digits as its factorization.

21211021101 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7070340370.

The product of its (nonzero) digits is 8, while the sum is 12.

Adding to 21211021101 its reverse (10112011212), we get a palindrome (31323032313).

The spelling of 21211021101 in words is "twenty-one billion, two hundred eleven million, twenty-one thousand, one hundred one".