210121211101 has 2 divisors, whose sum is σ = 210121211102. Its totient is φ = 210121211100.

The previous prime is 210121211059. The next prime is 210121211107. The reversal of 210121211101 is 101112121012.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 181821224025 + 28299987076 = 426405^2 + 168226^2 .

It is a cyclic number.

It is not a de Polignac number, because 210121211101 - 2³⁷ = 72682257629 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (210121211107) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 105060605550 + 105060605551.

It is an arithmetic number, because the mean of its divisors is an integer number (105060605551).

Almost surely, 2^210121211101 is an apocalyptic number.

It is an amenable number.

210121211101 is a deficient number, since it is larger than the sum of its proper divisors (1).

210121211101 is an equidigital number, since it uses as much as digits as its factorization.

210121211101 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 8, while the sum is 13.

Adding to 210121211101 its reverse (101112121012), we get a palindrome (311233332113).

The spelling of 210121211101 in words is "two hundred ten billion, one hundred twenty-one million, two hundred eleven thousand, one hundred one".