1205266649 has 2 divisors, whose sum is σ = 1205266650. Its totient is φ = 1205266648.

The previous prime is 1205266619. The next prime is 1205266717. The reversal of 1205266649 is 9466625021.

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., 1205131225 + 135424 = 34715^2 + 368^2 .

It is a cyclic number.

It is not a de Polignac number, because 1205266649 - 2²⁰ = 1204218073 is a prime.

It is not a weakly prime, because it can be changed into another prime (1205266619) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 602633324 + 602633325.

It is an arithmetic number, because the mean of its divisors is an integer number (602633325).

Almost surely, 2^1205266649 is an apocalyptic number.

It is an amenable number.

1205266649 is a deficient number, since it is larger than the sum of its proper divisors (1).

1205266649 is an equidigital number, since it uses as much as digits as its factorization.

1205266649 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 155520, while the sum is 41.

The square root of 1205266649 is about 34716.9504565133. The cubic root of 1205266649 is about 1064.2109252750.

The spelling of 1205266649 in words is "one billion, two hundred five million, two hundred sixty-six thousand, six hundred forty-nine".