12101220421 has 2 divisors, whose sum is σ = 12101220422. Its totient is φ = 12101220420.

The previous prime is 12101220401. The next prime is 12101220451. The reversal of 12101220421 is 12402210121.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 11574747396 + 526473025 = 107586^2 + 22945^2 .

It is a cyclic number.

It is not a de Polignac number, because 12101220421 - 2¹³ = 12101212229 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 12101220395 and 12101220404.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (12101220401) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6050610210 + 6050610211.

It is an arithmetic number, because the mean of its divisors is an integer number (6050610211).

Almost surely, 2^12101220421 is an apocalyptic number.

It is an amenable number.

12101220421 is a deficient number, since it is larger than the sum of its proper divisors (1).

12101220421 is an equidigital number, since it uses as much as digits as its factorization.

12101220421 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 64, while the sum is 16.

Adding to 12101220421 its reverse (12402210121), we get a palindrome (24503430542).

The spelling of 12101220421 in words is "twelve billion, one hundred one million, two hundred twenty thousand, four hundred twenty-one".