263998513 has 4 divisors (see below), whose sum is σ = 273101940. Its totient is φ = 254895088.

The previous prime is 263998489. The next prime is 263998517. The reversal of 263998513 is 315899362.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 97278769 + 166719744 = 9863^2 + 12912^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-263998513 is a prime.

It is a super-2 number, since 2×263998513² = 139390429732422338, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (263998517) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4551670 + ... + 4551727.

It is an arithmetic number, because the mean of its divisors is an integer number (68275485).

Almost surely, 2^263998513 is an apocalyptic number.

It is an amenable number.

263998513 is a deficient number, since it is larger than the sum of its proper divisors (9103427).

263998513 is an equidigital number, since it uses as much as digits as its factorization.

263998513 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9103426.

The product of its digits is 349920, while the sum is 46.

The square root of 263998513 is about 16248.0310499457. The cubic root of 263998513 is about 641.5056615516.

The spelling of 263998513 in words is "two hundred sixty-three million, nine hundred ninety-eight thousand, five hundred thirteen".