263936921 has 2 divisors, whose sum is σ = 263936922. Its totient is φ = 263936920.

The previous prime is 263936879. The next prime is 263936941. The reversal of 263936921 is 129639362.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 254083600 + 9853321 = 15940^2 + 3139^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-263936921 is a prime.

It is not a weakly prime, because it can be changed into another prime (263936941) 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, 131968460 + 131968461.

It is an arithmetic number, because the mean of its divisors is an integer number (131968461).

Almost surely, 2^263936921 is an apocalyptic number.

It is an amenable number.

263936921 is a deficient number, since it is larger than the sum of its proper divisors (1).

263936921 is an equidigital number, since it uses as much as digits as its factorization.

263936921 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 104976, while the sum is 41.

The square root of 263936921 is about 16246.1355712674. The cubic root of 263936921 is about 641.4557689854.

The spelling of 263936921 in words is "two hundred sixty-three million, nine hundred thirty-six thousand, nine hundred twenty-one".