505978358549 has 2 divisors, whose sum is σ = 505978358550. Its totient is φ = 505978358548.

The previous prime is 505978358497. The next prime is 505978358563. The reversal of 505978358549 is 945853879505.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 498991070449 + 6987288100 = 706393^2 + 83590^2 .

It is a cyclic number.

It is not a de Polignac number, because 505978358549 - 2¹⁶ = 505978293013 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (505978348549) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 252989179274 + 252989179275.

It is an arithmetic number, because the mean of its divisors is an integer number (252989179275).

Almost surely, 2^505978358549 is an apocalyptic number.

It is an amenable number.

505978358549 is a deficient number, since it is larger than the sum of its proper divisors (1).

505978358549 is an equidigital number, since it uses as much as digits as its factorization.

505978358549 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 272160000, while the sum is 68.

The spelling of 505978358549 in words is "five hundred five billion, nine hundred seventy-eight million, three hundred fifty-eight thousand, five hundred forty-nine".