1221220229 has 2 divisors, whose sum is σ = 1221220230. Its totient is φ = 1221220228.

The previous prime is 1221220199. The next prime is 1221220271. The reversal of 1221220229 is 9220221221.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 973315204 + 247905025 = 31198^2 + 15745^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1221220229 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1221220289) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 610610114 + 610610115.

It is an arithmetic number, because the mean of its divisors is an integer number (610610115).

Almost surely, 2^1221220229 is an apocalyptic number.

It is an amenable number.

1221220229 is a deficient number, since it is larger than the sum of its proper divisors (1).

1221220229 is an equidigital number, since it uses as much as digits as its factorization.

1221220229 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 576, while the sum is 23.

The square root of 1221220229 is about 34945.9615549494. The cubic root of 1221220229 is about 1068.8858548775.

The spelling of 1221220229 in words is "one billion, two hundred twenty-one million, two hundred twenty thousand, two hundred twenty-nine".