210121202100001 has 2 divisors, whose sum is σ = 210121202100002. Its totient is φ = 210121202100000.

The previous prime is 210121202099999. The next prime is 210121202100041. The reversal of 210121202100001 is 100001202121012.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 162934400459776 + 47186801640225 = 12764576^2 + 6869265^2 .

It is a cyclic number.

It is not a de Polignac number, because 210121202100001 - 2¹ = 210121202099999 is a prime.

Together with 210121202099999, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (210121202100041) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 105060601050000 + 105060601050001.

It is an arithmetic number, because the mean of its divisors is an integer number (105060601050001).

Almost surely, 2^{210121202100001} is an apocalyptic number.

It is an amenable number.

210121202100001 is a deficient number, since it is larger than the sum of its proper divisors (1).

210121202100001 is an equidigital number, since it uses as much as digits as its factorization.

210121202100001 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 16, while the sum is 13.

Adding to 210121202100001 its reverse (100001202121012), we get a palindrome (310122404221013).

The spelling of 210121202100001 in words is "two hundred ten trillion, one hundred twenty-one billion, two hundred two million, one hundred thousand, one".