1220120221 has 2 divisors, whose sum is σ = 1220120222. Its totient is φ = 1220120220.

The previous prime is 1220120201. The next prime is 1220120249. The reversal of 1220120221 is 1220210221.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 948332025 + 271788196 = 30795^2 + 16486^2 .

It is a cyclic number.

It is not a de Polignac number, because 1220120221 - 2¹³ = 1220112029 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1220120201) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 610060110 + 610060111.

It is an arithmetic number, because the mean of its divisors is an integer number (610060111).

Almost surely, 2^1220120221 is an apocalyptic number.

It is an amenable number.

1220120221 is a deficient number, since it is larger than the sum of its proper divisors (1).

1220120221 is an equidigital number, since it uses as much as digits as its factorization.

1220120221 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 32, while the sum is 13.

The square root of 1220120221 is about 34930.2193093602. The cubic root of 1220120221 is about 1068.5648272782.

Adding to 1220120221 its reverse (1220210221), we get a palindrome (2440330442).

Subtracting 1220120221 from its reverse (1220210221), we obtain a square (90000 = 300²).

The spelling of 1220120221 in words is "one billion, two hundred twenty million, one hundred twenty thousand, two hundred twenty-one".