1213221277 has 2 divisors, whose sum is σ = 1213221278. Its totient is φ = 1213221276.

The previous prime is 1213221203. The next prime is 1213221299. The reversal of 1213221277 is 7721223121.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1084648356 + 128572921 = 32934^2 + 11339^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1213221277 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1213221077) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 606610638 + 606610639.

It is an arithmetic number, because the mean of its divisors is an integer number (606610639).

Almost surely, 2^1213221277 is an apocalyptic number.

It is an amenable number.

1213221277 is a deficient number, since it is larger than the sum of its proper divisors (1).

1213221277 is an equidigital number, since it uses as much as digits as its factorization.

1213221277 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2352, while the sum is 28.

The square root of 1213221277 is about 34831.3260873025. The cubic root of 1213221277 is about 1066.5470186868.

Adding to 1213221277 its reverse (7721223121), we get a palindrome (8934444398).

The spelling of 1213221277 in words is "one billion, two hundred thirteen million, two hundred twenty-one thousand, two hundred seventy-seven".