21212231101 has 4 divisors (see below), whose sum is σ = 21212741212. Its totient is φ = 21211720992.

The previous prime is 21212231039. The next prime is 21212231113. The reversal of 21212231101 is 10113221212.

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 20641068900 + 571162201 = 143670^2 + 23899^2 .

It is a cyclic number.

It is not a de Polignac number, because 21212231101 - 2¹¹ = 21212229053 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 (21212231171) 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, 186546 + ... + 277891.

It is an arithmetic number, because the mean of its divisors is an integer number (5303185303).

Almost surely, 2^21212231101 is an apocalyptic number.

It is an amenable number.

21212231101 is a deficient number, since it is larger than the sum of its proper divisors (510111).

21212231101 is an equidigital number, since it uses as much as digits as its factorization.

21212231101 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 510110.

The product of its (nonzero) digits is 48, while the sum is 16.

Adding to 21212231101 its reverse (10113221212), we get a palindrome (31325452313).

The spelling of 21212231101 in words is "twenty-one billion, two hundred twelve million, two hundred thirty-one thousand, one hundred one".