263007991 has 2 divisors, whose sum is σ = 263007992. Its totient is φ = 263007990.

The previous prime is 263007961. The next prime is 263008001. The reversal of 263007991 is 199700362.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 263007991 - 2⁵ = 263007959 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 263007991.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (263007961) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 131503995 + 131503996.

It is an arithmetic number, because the mean of its divisors is an integer number (131503996).

Almost surely, 2^263007991 is an apocalyptic number.

263007991 is a deficient number, since it is larger than the sum of its proper divisors (1).

263007991 is an equidigital number, since it uses as much as digits as its factorization.

263007991 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 20412, while the sum is 37.

The square root of 263007991 is about 16217.5211114399. The cubic root of 263007991 is about 640.7023466270.

The spelling of 263007991 in words is "two hundred sixty-three million, seven thousand, nine hundred ninety-one".