781968804101 has 2 divisors, whose sum is σ = 781968804102. Its totient is φ = 781968804100.

The previous prime is 781968804047. The next prime is 781968804151. The reversal of 781968804101 is 101408869187.

It is a Cunningham number, because it is equal to 884290²+1.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 781968804100 + 1 = 884290^2 + 1^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-781968804101 is a prime.

It is a super-2 number, since 2×781968804101² (a number of 25 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (781968804151) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 390984402050 + 390984402051.

It is an arithmetic number, because the mean of its divisors is an integer number (390984402051).

Almost surely, 2^781968804101 is an apocalyptic number.

It is an amenable number.

781968804101 is a deficient number, since it is larger than the sum of its proper divisors (1).

781968804101 is an equidigital number, since it uses as much as digits as its factorization.

781968804101 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 774144, while the sum is 53.

The spelling of 781968804101 in words is "seven hundred eighty-one billion, nine hundred sixty-eight million, eight hundred four thousand, one hundred one".