121103200210021 has 4 divisors (see below), whose sum is σ = 128226917869452. Its totient is φ = 113979482550592.

The previous prime is 121103200210007. The next prime is 121103200210037. The reversal of 121103200210021 is 120012002301121.

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 113812390187521 + 7290810022500 = 10668289^2 + 2700150^2 .

It is a cyclic number.

It is not a de Polignac number, because 121103200210021 - 2²⁵ = 121103166655589 is a prime.

It is a super-2 number, since 2×121103200210021² (a number of 29 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 121103200209977 and 121103200210004.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121103200214021) 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, 3561858829690 + ... + 3561858829723.

It is an arithmetic number, because the mean of its divisors is an integer number (32056729467363).

Almost surely, 2^{121103200210021} is an apocalyptic number.

It is an amenable number.

121103200210021 is a deficient number, since it is larger than the sum of its proper divisors (7123717659431).

121103200210021 is an equidigital number, since it uses as much as digits as its factorization.

121103200210021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7123717659430.

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

Adding to 121103200210021 its reverse (120012002301121), we get a palindrome (241115202511142).

The spelling of 121103200210021 in words is "one hundred twenty-one trillion, one hundred three billion, two hundred million, two hundred ten thousand, twenty-one".