253681865581 has 2 divisors, whose sum is σ = 253681865582. Its totient is φ = 253681865580.

The previous prime is 253681865579. The next prime is 253681865623. The reversal of 253681865581 is 185568186352.

253681865581 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 249709084681 + 3972780900 = 499709^2 + 63030^2 .

It is a cyclic number.

It is not a de Polignac number, because 253681865581 - 2¹ = 253681865579 is a prime.

It is a super-2 number, since 2×253681865581² (a number of 24 digits) contains 22 as substring.

Together with 253681865579, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (253681865881) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 126840932790 + 126840932791.

It is an arithmetic number, because the mean of its divisors is an integer number (126840932791).

Almost surely, 2^253681865581 is an apocalyptic number.

It is an amenable number.

253681865581 is a deficient number, since it is larger than the sum of its proper divisors (1).

253681865581 is an equidigital number, since it uses as much as digits as its factorization.

253681865581 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 13824000, while the sum is 58.

The spelling of 253681865581 in words is "two hundred fifty-three billion, six hundred eighty-one million, eight hundred sixty-five thousand, five hundred eighty-one".