421221202122101 has 4 divisors (see below), whose sum is σ = 421229903469900. Its totient is φ = 421212500774304.

The previous prime is 421221202122059. The next prime is 421221202122103. The reversal of 421221202122101 is 101221202122124.

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 391279020039076 + 29942182083025 = 19780774^2 + 5471945^2 .

It is a cyclic number.

It is not a de Polignac number, because 421221202122101 - 2⁴² = 416823155610997 is a prime.

It is a super-2 number, since 2×421221202122101² (a number of 30 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (421221202122103) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4350601286 + ... + 4350698103.

It is an arithmetic number, because the mean of its divisors is an integer number (105307475867475).

Almost surely, 2^{421221202122101} is an apocalyptic number.

It is an amenable number.

421221202122101 is a deficient number, since it is larger than the sum of its proper divisors (8701347799).

421221202122101 is an equidigital number, since it uses as much as digits as its factorization.

421221202122101 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8701347798.

The product of its (nonzero) digits is 512, while the sum is 23.

Adding to 421221202122101 its sum of digits (23), we get a palindrome (421221202122124).

Adding to 421221202122101 its reverse (101221202122124), we get a palindrome (522442404244225).

The spelling of 421221202122101 in words is "four hundred twenty-one trillion, two hundred twenty-one billion, two hundred two million, one hundred twenty-two thousand, one hundred one".