1222457861 has 2 divisors, whose sum is σ = 1222457862. Its totient is φ = 1222457860.

The previous prime is 1222457801. The next prime is 1222457881. The reversal of 1222457861 is 1687542221.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 798345025 + 424112836 = 28255^2 + 20594^2 .

It is an emirp because it is prime and its reverse (1687542221) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1222457861 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 (1222457801) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 611228930 + 611228931.

It is an arithmetic number, because the mean of its divisors is an integer number (611228931).

Almost surely, 2^1222457861 is an apocalyptic number.

It is an amenable number.

1222457861 is a deficient number, since it is larger than the sum of its proper divisors (1).

1222457861 is an equidigital number, since it uses as much as digits as its factorization.

1222457861 is an evil number, because the sum of its binary digits is even.

The product of its digits is 53760, while the sum is 38.

The square root of 1222457861 is about 34963.6648679740. The cubic root of 1222457861 is about 1069.2468164442.

The spelling of 1222457861 in words is "one billion, two hundred twenty-two million, four hundred fifty-seven thousand, eight hundred sixty-one".