1263520649 has 2 divisors, whose sum is σ = 1263520650. Its totient is φ = 1263520648.

The previous prime is 1263520619. The next prime is 1263520681. The reversal of 1263520649 is 9460253621.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1255426624 + 8094025 = 35432^2 + 2845^2 .

It is a cyclic number.

It is not a de Polignac number, because 1263520649 - 2²⁰ = 1262472073 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (1263520619) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 631760324 + 631760325.

It is an arithmetic number, because the mean of its divisors is an integer number (631760325).

Almost surely, 2^1263520649 is an apocalyptic number.

It is an amenable number.

1263520649 is a deficient number, since it is larger than the sum of its proper divisors (1).

1263520649 is an equidigital number, since it uses as much as digits as its factorization.

1263520649 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 77760, while the sum is 38.

The square root of 1263520649 is about 35546.0356298702. The cubic root of 1263520649 is about 1081.0873391180.

The spelling of 1263520649 in words is "one billion, two hundred sixty-three million, five hundred twenty thousand, six hundred forty-nine".