210121221121001 has 4 divisors (see below), whose sum is σ = 210121987933572. Its totient is φ = 210120454308432.

The previous prime is 210121221120997. The next prime is 210121221121003. The reversal of 210121221121001 is 100121122121012.

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 121736798233600 + 88384422887401 = 11033440^2 + 9401299^2 .

It is a cyclic number.

It is not a de Polignac number, because 210121221121001 - 2² = 210121221120997 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (210121221121003) 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, 382995110 + ... + 383543343.

It is an arithmetic number, because the mean of its divisors is an integer number (52530496983393).

Almost surely, 2^{210121221121001} is an apocalyptic number.

It is an amenable number.

210121221121001 is a deficient number, since it is larger than the sum of its proper divisors (766812571).

210121221121001 is an equidigital number, since it uses as much as digits as its factorization.

210121221121001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 766812570.

The product of its (nonzero) digits is 32, while the sum is 17.

Adding to 210121221121001 its reverse (100121122121012), we get a palindrome (310242343242013).

The spelling of 210121221121001 in words is "two hundred ten trillion, one hundred twenty-one billion, two hundred twenty-one million, one hundred twenty-one thousand, one".