21211212101 has 8 divisors (see below), whose sum is σ = 21515613984. Its totient is φ = 20908661200.

The previous prime is 21211212083. The next prime is 21211212107. The reversal of 21211212101 is 10121211212.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21211212101 - 2¹⁸ = 21210949957 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21211212107) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 439655 + ... + 485508.

It is an arithmetic number, because the mean of its divisors is an integer number (2689451748).

Almost surely, 2^21211212101 is an apocalyptic number.

It is an amenable number.

21211212101 is a deficient number, since it is larger than the sum of its proper divisors (304401883).

21211212101 is a wasteful number, since it uses less digits than its factorization.

21211212101 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 925491.

The product of its (nonzero) digits is 16, while the sum is 14.

Adding to 21211212101 its reverse (10121211212), we get a palindrome (31332423313).

It can be divided in two parts, 21211212 and 101, that multiplied together give a palindrome (2142332412).

The spelling of 21211212101 in words is "twenty-one billion, two hundred eleven million, two hundred twelve thousand, one hundred one".