1205263649 has 8 divisors (see below), whose sum is σ = 1209290472. Its totient is φ = 1201244800.

The previous prime is 1205263643. The next prime is 1205263669. The reversal of 1205263649 is 9463625021.

It can be written as a sum of positive squares in 4 ways, for example, as 85692049 + 1119571600 = 9257^2 + 33460^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1205263649 - 2⁸ = 1205263393 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1205263643) 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 in 7 ways as a sum of consecutive naturals, for example, 456437 + ... + 459069.

It is an arithmetic number, because the mean of its divisors is an integer number (151161309).

Almost surely, 2^1205263649 is an apocalyptic number.

It is an amenable number.

1205263649 is a deficient number, since it is larger than the sum of its proper divisors (4026823).

1205263649 is an equidigital number, since it uses as much as digits as its factorization.

1205263649 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3987.

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

The square root of 1205263649 is about 34716.9072499265. The cubic root of 1205263649 is about 1064.2100423070.

The spelling of 1205263649 in words is "one billion, two hundred five million, two hundred sixty-three thousand, six hundred forty-nine".