1221030257 has 2 divisors, whose sum is σ = 1221030258. Its totient is φ = 1221030256.

The previous prime is 1221030199. The next prime is 1221030259. The reversal of 1221030257 is 7520301221.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 792084736 + 428945521 = 28144^2 + 20711^2 .

It is a cyclic number.

It is not a de Polignac number, because 1221030257 - 2⁸ = 1221030001 is a prime.

Together with 1221030259, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (1221030259) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 610515128 + 610515129.

It is an arithmetic number, because the mean of its divisors is an integer number (610515129).

Almost surely, 2^1221030257 is an apocalyptic number.

It is an amenable number.

1221030257 is a deficient number, since it is larger than the sum of its proper divisors (1).

1221030257 is an equidigital number, since it uses as much as digits as its factorization.

1221030257 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 840, while the sum is 23.

The square root of 1221030257 is about 34943.2433669229. The cubic root of 1221030257 is about 1068.8304270061.

Adding to 1221030257 its reverse (7520301221), we get a palindrome (8741331478).

The spelling of 1221030257 in words is "one billion, two hundred twenty-one million, thirty thousand, two hundred fifty-seven".