1320778049 has 2 divisors, whose sum is σ = 1320778050. Its totient is φ = 1320778048.

The previous prime is 1320778009. The next prime is 1320778051. The reversal of 1320778049 is 9408770231.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1235030449 + 85747600 = 35143^2 + 9260^2 .

It is a cyclic number.

It is not a de Polignac number, because 1320778049 - 2⁸ = 1320777793 is a prime.

Together with 1320778051, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 1320777997 and 1320778015.

It is not a weakly prime, because it can be changed into another prime (1320778009) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 660389024 + 660389025.

It is an arithmetic number, because the mean of its divisors is an integer number (660389025).

Almost surely, 2^1320778049 is an apocalyptic number.

It is an amenable number.

1320778049 is a deficient number, since it is larger than the sum of its proper divisors (1).

1320778049 is an equidigital number, since it uses as much as digits as its factorization.

1320778049 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 84672, while the sum is 41.

The square root of 1320778049 is about 36342.5102187507. The cubic root of 1320778049 is about 1097.1767958437.

The spelling of 1320778049 in words is "one billion, three hundred twenty million, seven hundred seventy-eight thousand, forty-nine".