263136661 has 2 divisors, whose sum is σ = 263136662. Its totient is φ = 263136660.

The previous prime is 263136631. The next prime is 263136697. The reversal of 263136661 is 166631362.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 166900561 + 96236100 = 12919^2 + 9810^2 .

It is a cyclic number.

It is not a de Polignac number, because 263136661 - 2¹³ = 263128469 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (263136631) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 131568330 + 131568331.

It is an arithmetic number, because the mean of its divisors is an integer number (131568331).

Almost surely, 2^263136661 is an apocalyptic number.

It is an amenable number.

263136661 is a deficient number, since it is larger than the sum of its proper divisors (1).

263136661 is an equidigital number, since it uses as much as digits as its factorization.

263136661 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 23328, while the sum is 34.

The square root of 263136661 is about 16221.4876321501. The cubic root of 263136661 is about 640.8068120598.

The spelling of 263136661 in words is "two hundred sixty-three million, one hundred thirty-six thousand, six hundred sixty-one".