21211120001 has 2 divisors, whose sum is σ = 21211120002. Its totient is φ = 21211120000.

The previous prime is 21211119991. The next prime is 21211120013. The reversal of 21211120001 is 10002111212.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20894991601 + 316128400 = 144551^2 + 17780^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21211120001 is a prime.

It is a super-2 number, since 2×21211120001² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (21211120061) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10605560000 + 10605560001.

It is an arithmetic number, because the mean of its divisors is an integer number (10605560001).

Almost surely, 2^21211120001 is an apocalyptic number.

It is an amenable number.

21211120001 is a deficient number, since it is larger than the sum of its proper divisors (1).

21211120001 is an equidigital number, since it uses as much as digits as its factorization.

21211120001 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 8, while the sum is 11.

Adding to 21211120001 its reverse (10002111212), we get a palindrome (31213231213).

The spelling of 21211120001 in words is "twenty-one billion, two hundred eleven million, one hundred twenty thousand, one".