213991263 has 24 divisors (see below), whose sum is σ = 322285392. Its totient is φ = 136700928.

The previous prime is 213991247. The next prime is 213991273. The reversal of 213991263 is 362199312.

It is a happy number.

213991263 is a `hidden beast` number, since 2 + 1 + 399 + 1 + 263 = 666.

It is not a de Polignac number, because 213991263 - 2⁴ = 213991247 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (213991273) 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 in 23 ways as a sum of consecutive naturals, for example, 15295 + ... + 25727.

It is an arithmetic number, because the mean of its divisors is an integer number (13428558).

Almost surely, 2^213991263 is an apocalyptic number.

213991263 is a deficient number, since it is larger than the sum of its proper divisors (108294129).

213991263 is a wasteful number, since it uses less digits than its factorization.

213991263 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10535 (or 10532 counting only the distinct ones).

The product of its digits is 17496, while the sum is 36.

The square root of 213991263 is about 14628.4402107675. The cubic root of 213991263 is about 598.1342627208.

The spelling of 213991263 in words is "two hundred thirteen million, nine hundred ninety-one thousand, two hundred sixty-three".