28705090649 has 2 divisors, whose sum is σ = 28705090650. Its totient is φ = 28705090648.

The previous prime is 28705090639. The next prime is 28705090709. The reversal of 28705090649 is 94609050782.

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., 17308033600 + 11397057049 = 131560^2 + 106757^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28705090649 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 28705090597 and 28705090606.

It is not a weakly prime, because it can be changed into another prime (28705090639) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14352545324 + 14352545325.

It is an arithmetic number, because the mean of its divisors is an integer number (14352545325).

Almost surely, 2^28705090649 is an apocalyptic number.

It is an amenable number.

28705090649 is a deficient number, since it is larger than the sum of its proper divisors (1).

28705090649 is an equidigital number, since it uses as much as digits as its factorization.

28705090649 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1088640, while the sum is 50.

The spelling of 28705090649 in words is "twenty-eight billion, seven hundred five million, ninety thousand, six hundred forty-nine".