202121212122101 has 4 divisors (see below), whose sum is σ = 202121558337900. Its totient is φ = 202120865906304.

The previous prime is 202121212122097. The next prime is 202121212122143. The reversal of 202121212122101 is 101221212121202.

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 130174750642225 + 71946461479876 = 11409415^2 + 8482126^2 .

It is a cyclic number.

It is not a de Polignac number, because 202121212122101 - 2² = 202121212122097 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (202121212122301) 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, 172230716 + ... + 173400293.

It is an arithmetic number, because the mean of its divisors is an integer number (50530389584475).

Almost surely, 2^{202121212122101} is an apocalyptic number.

It is an amenable number.

202121212122101 is a deficient number, since it is larger than the sum of its proper divisors (346215799).

202121212122101 is an equidigital number, since it uses as much as digits as its factorization.

202121212122101 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 346215798.

The product of its (nonzero) digits is 128, while the sum is 20.

Adding to 202121212122101 its reverse (101221212121202), we get a palindrome (303342424243303).

The spelling of 202121212122101 in words is "two hundred two trillion, one hundred twenty-one billion, two hundred twelve million, one hundred twenty-two thousand, one hundred one".