647874920449 has 2 divisors, whose sum is σ = 647874920450. Its totient is φ = 647874920448.

The previous prime is 647874920447. The next prime is 647874920507. The reversal of 647874920449 is 944029478746.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 531685972224 + 116188948225 = 729168^2 + 340865^2 .

It is a cyclic number.

It is not a de Polignac number, because 647874920449 - 2¹ = 647874920447 is a prime.

Together with 647874920447, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (647874920443) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 323937460224 + 323937460225.

It is an arithmetic number, because the mean of its divisors is an integer number (323937460225).

Almost surely, 2^647874920449 is an apocalyptic number.

It is an amenable number.

647874920449 is a deficient number, since it is larger than the sum of its proper divisors (1).

647874920449 is an equidigital number, since it uses as much as digits as its factorization.

647874920449 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 97542144, while the sum is 64.

The spelling of 647874920449 in words is "six hundred forty-seven billion, eight hundred seventy-four million, nine hundred twenty thousand, four hundred forty-nine".