266231054651521 has 2 divisors, whose sum is σ = 266231054651522. Its totient is φ = 266231054651520.

The previous prime is 266231054651509. The next prime is 266231054651539. The reversal of 266231054651521 is 125156450132662.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 138781947330625 + 127449107320896 = 11780575^2 + 11289336^2 .

It is a cyclic number.

It is not a de Polignac number, because 266231054651521 - 2¹⁷ = 266231054520449 is a prime.

It is a super-2 number, since 2×266231054651521² (a number of 30 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (266231054651321) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 133115527325760 + 133115527325761.

It is an arithmetic number, because the mean of its divisors is an integer number (133115527325761).

Almost surely, 2^{266231054651521} is an apocalyptic number.

It is an amenable number.

266231054651521 is a deficient number, since it is larger than the sum of its proper divisors (1).

266231054651521 is an equidigital number, since it uses as much as digits as its factorization.

266231054651521 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2592000, while the sum is 49.

The spelling of 266231054651521 in words is "two hundred sixty-six trillion, two hundred thirty-one billion, fifty-four million, six hundred fifty-one thousand, five hundred twenty-one".