263839090681 has 2 divisors, whose sum is σ = 263839090682. Its totient is φ = 263839090680.

The previous prime is 263839090663. The next prime is 263839090709. The reversal of 263839090681 is 186090938362.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 259344729081 + 4494361600 = 509259^2 + 67040^2 .

It is a cyclic number.

It is not a de Polignac number, because 263839090681 - 2¹⁷ = 263838959609 is a prime.

It is a super-2 number, since 2×263839090681² (a number of 24 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (263839090601) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 131919545340 + 131919545341.

It is an arithmetic number, because the mean of its divisors is an integer number (131919545341).

Almost surely, 2^263839090681 is an apocalyptic number.

It is an amenable number.

263839090681 is a deficient number, since it is larger than the sum of its proper divisors (1).

263839090681 is an equidigital number, since it uses as much as digits as its factorization.

263839090681 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3359232, while the sum is 55.

The spelling of 263839090681 in words is "two hundred sixty-three billion, eight hundred thirty-nine million, ninety thousand, six hundred eighty-one".