1281230777 has 2 divisors, whose sum is σ = 1281230778. Its totient is φ = 1281230776.

The previous prime is 1281230761. The next prime is 1281230791. The reversal of 1281230777 is 7770321821.

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., 958273936 + 322956841 = 30956^2 + 17971^2 .

It is an emirp because it is prime and its reverse (7770321821) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1281230777 - 2⁴ = 1281230761 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1281230777.

It is not a weakly prime, because it can be changed into another prime (1281230707) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 640615388 + 640615389.

It is an arithmetic number, because the mean of its divisors is an integer number (640615389).

Almost surely, 2^1281230777 is an apocalyptic number.

It is an amenable number.

1281230777 is a deficient number, since it is larger than the sum of its proper divisors (1).

1281230777 is an equidigital number, since it uses as much as digits as its factorization.

1281230777 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 32928, while the sum is 38.

The square root of 1281230777 is about 35794.2841386722. The cubic root of 1281230777 is about 1086.1149396122.

The spelling of 1281230777 in words is "one billion, two hundred eighty-one million, two hundred thirty thousand, seven hundred seventy-seven".