21212106001 has 2 divisors, whose sum is σ = 21212106002. Its totient is φ = 21212106000.

The previous prime is 21212105977. The next prime is 21212106029. The reversal of 21212106001 is 10060121212.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 21125169025 + 86936976 = 145345^2 + 9324^2 .

It is a cyclic number.

It is not a de Polignac number, because 21212106001 - 2²³ = 21203717393 is a prime.

It is a super-3 number, since 3×21212106001³ (a number of 32 digits) contains 333 as substring.

It is not a weakly prime, because it can be changed into another prime (21212100001) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10606053000 + 10606053001.

It is an arithmetic number, because the mean of its divisors is an integer number (10606053001).

Almost surely, 2^21212106001 is an apocalyptic number.

It is an amenable number.

21212106001 is a deficient number, since it is larger than the sum of its proper divisors (1).

21212106001 is an equidigital number, since it uses as much as digits as its factorization.

21212106001 is an odious number, because the sum of its binary digits is odd.

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

Adding to 21212106001 its reverse (10060121212), we get a palindrome (31272227213).

The spelling of 21212106001 in words is "twenty-one billion, two hundred twelve million, one hundred six thousand, one".