778964943553 has 2 divisors, whose sum is σ = 778964943554. Its totient is φ = 778964943552.

The previous prime is 778964943479. The next prime is 778964943557. The reversal of 778964943553 is 355349469877.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 693810700209 + 85154243344 = 832953^2 + 291812^2 .

It is a cyclic number.

It is not a de Polignac number, because 778964943553 - 2⁹ = 778964943041 is a prime.

It is not a weakly prime, because it can be changed into another prime (778964943557) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 389482471776 + 389482471777.

It is an arithmetic number, because the mean of its divisors is an integer number (389482471777).

Almost surely, 2^778964943553 is an apocalyptic number.

It is an amenable number.

778964943553 is a deficient number, since it is larger than the sum of its proper divisors (1).

778964943553 is an equidigital number, since it uses as much as digits as its factorization.

778964943553 is an evil number, because the sum of its binary digits is even.

The product of its digits is 685843200, while the sum is 70.

The spelling of 778964943553 in words is "seven hundred seventy-eight billion, nine hundred sixty-four million, nine hundred forty-three thousand, five hundred fifty-three".