1299645901 has 2 divisors, whose sum is σ = 1299645902. Its totient is φ = 1299645900.

The previous prime is 1299645899. The next prime is 1299646001. The reversal of 1299645901 is 1095469921.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 662032900 + 637613001 = 25730^2 + 25251^2 .

It is a cyclic number.

It is not a de Polignac number, because 1299645901 - 2¹ = 1299645899 is a prime.

It is a super-2 number, since 2×1299645901² = 3378158935972203602, which contains 22 as substring.

Together with 1299645899, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1299645601) 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, 649822950 + 649822951.

It is an arithmetic number, because the mean of its divisors is an integer number (649822951).

Almost surely, 2^1299645901 is an apocalyptic number.

It is an amenable number.

1299645901 is a deficient number, since it is larger than the sum of its proper divisors (1).

1299645901 is an equidigital number, since it uses as much as digits as its factorization.

1299645901 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 174960, while the sum is 46.

The square root of 1299645901 is about 36050.6019505916. The cubic root of 1299645901 is about 1091.2937814656.

The spelling of 1299645901 in words is "one billion, two hundred ninety-nine million, six hundred forty-five thousand, nine hundred one".