1228620961 has 2 divisors, whose sum is σ = 1228620962. Its totient is φ = 1228620960.

The previous prime is 1228620919. The next prime is 1228620979. The reversal of 1228620961 is 1690268221.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 913913361 + 314707600 = 30231^2 + 17740^2 .

It is an emirp because it is prime and its reverse (1690268221) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1228620961 - 2²⁹ = 691750049 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1228620961.

It is not a weakly prime, because it can be changed into another prime (1228626961) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 614310480 + 614310481.

It is an arithmetic number, because the mean of its divisors is an integer number (614310481).

Almost surely, 2^1228620961 is an apocalyptic number.

It is an amenable number.

1228620961 is a deficient number, since it is larger than the sum of its proper divisors (1).

1228620961 is an equidigital number, since it uses as much as digits as its factorization.

1228620961 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 20736, while the sum is 37.

The square root of 1228620961 is about 35051.6898451416. The cubic root of 1228620961 is about 1071.0406973765.

The spelling of 1228620961 in words is "one billion, two hundred twenty-eight million, six hundred twenty thousand, nine hundred sixty-one".