1210121203121 has 4 divisors (see below), whose sum is σ = 1251849520500. Its totient is φ = 1168392885744.

The previous prime is 1210121203117. The next prime is 1210121203147. The reversal of 1210121203121 is 1213021210121.

It is a happy number.

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 433607763121 + 776513440000 = 658489^2 + 881200^2 .

It is a cyclic number.

It is not a de Polignac number, because 1210121203121 - 2² = 1210121203117 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1210121203121.

It is not an unprimeable number, because it can be changed into a prime (1210121205121) 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, 20864158646 + ... + 20864158703.

It is an arithmetic number, because the mean of its divisors is an integer number (312962380125).

Almost surely, 2^{1210121203121} is an apocalyptic number.

It is an amenable number.

1210121203121 is a deficient number, since it is larger than the sum of its proper divisors (41728317379).

1210121203121 is an equidigital number, since it uses as much as digits as its factorization.

1210121203121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 41728317378.

The product of its (nonzero) digits is 48, while the sum is 17.

Adding to 1210121203121 its reverse (1213021210121), we get a palindrome (2423142413242).

The spelling of 1210121203121 in words is "one trillion, two hundred ten billion, one hundred twenty-one million, two hundred three thousand, one hundred twenty-one".