259781857381 has 2 divisors, whose sum is σ = 259781857382. Its totient is φ = 259781857380.

The previous prime is 259781857271. The next prime is 259781857399. The reversal of 259781857381 is 183758187952.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 231029229025 + 28752628356 = 480655^2 + 169566^2 .

It is a cyclic number.

It is not a de Polignac number, because 259781857381 - 2⁷ = 259781857253 is a prime.

It is a super-2 number, since 2×259781857381² (a number of 24 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (259781857781) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 129890928690 + 129890928691.

It is an arithmetic number, because the mean of its divisors is an integer number (129890928691).

Almost surely, 2^259781857381 is an apocalyptic number.

It is an amenable number.

259781857381 is a deficient number, since it is larger than the sum of its proper divisors (1).

259781857381 is an equidigital number, since it uses as much as digits as its factorization.

259781857381 is an evil number, because the sum of its binary digits is even.

The product of its digits is 33868800, while the sum is 64.

The spelling of 259781857381 in words is "two hundred fifty-nine billion, seven hundred eighty-one million, eight hundred fifty-seven thousand, three hundred eighty-one".