263970991 has 2 divisors, whose sum is σ = 263970992. Its totient is φ = 263970990.

The previous prime is 263970923. The next prime is 263971003. The reversal of 263970991 is 199079362.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 263970991 - 2⁹ = 263970479 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (263970911) 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, 131985495 + 131985496.

It is an arithmetic number, because the mean of its divisors is an integer number (131985496).

Almost surely, 2^263970991 is an apocalyptic number.

263970991 is a deficient number, since it is larger than the sum of its proper divisors (1).

263970991 is an equidigital number, since it uses as much as digits as its factorization.

263970991 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 183708, while the sum is 46.

The square root of 263970991 is about 16247.1840944823. The cubic root of 263970991 is about 641.4833683295.

The spelling of 263970991 in words is "two hundred sixty-three million, nine hundred seventy thousand, nine hundred ninety-one".