12155030221 has 2 divisors, whose sum is σ = 12155030222. Its totient is φ = 12155030220.

The previous prime is 12155030137. The next prime is 12155030233. The reversal of 12155030221 is 12203055121.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 6836974596 + 5318055625 = 82686^2 + 72925^2 .

It is a cyclic number.

It is not a de Polignac number, because 12155030221 - 2²⁷ = 12020812493 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 12155030192 and 12155030201.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (12155037221) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6077515110 + 6077515111.

It is an arithmetic number, because the mean of its divisors is an integer number (6077515111).

Almost surely, 2^12155030221 is an apocalyptic number.

It is an amenable number.

12155030221 is a deficient number, since it is larger than the sum of its proper divisors (1).

12155030221 is an equidigital number, since it uses as much as digits as its factorization.

12155030221 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 600, while the sum is 22.

Adding to 12155030221 its reverse (12203055121), we get a palindrome (24358085342).

Subtracting 12155030221 from its reverse (12203055121), we obtain a triangular number (48024900 = T₉₈₀₀).

The spelling of 12155030221 in words is "twelve billion, one hundred fifty-five million, thirty thousand, two hundred twenty-one".