781255242389 has 2 divisors, whose sum is σ = 781255242390. Its totient is φ = 781255242388.

The previous prime is 781255242377. The next prime is 781255242401. The reversal of 781255242389 is 983242552187.

It is a balanced prime because it is at equal distance from previous prime (781255242377) and next prime (781255242401).

It can be written as a sum of positive squares in only one way, i.e., 497048970289 + 284206272100 = 705017^2 + 533110^2 .

It is a cyclic number.

It is not a de Polignac number, because 781255242389 - 2²⁴ = 781238465173 is a prime.

It is a super-2 number, since 2×781255242389² (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 (781255242349) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 390627621194 + 390627621195.

It is an arithmetic number, because the mean of its divisors is an integer number (390627621195).

Almost surely, 2^781255242389 is an apocalyptic number.

It is an amenable number.

781255242389 is a deficient number, since it is larger than the sum of its proper divisors (1).

781255242389 is an equidigital number, since it uses as much as digits as its factorization.

781255242389 is an evil number, because the sum of its binary digits is even.

The product of its digits is 9676800, while the sum is 56.

The spelling of 781255242389 in words is "seven hundred eighty-one billion, two hundred fifty-five million, two hundred forty-two thousand, three hundred eighty-nine".