247805213 has 4 divisors (see below), whose sum is σ = 248452608. Its totient is φ = 247157820.

The previous prime is 247805183. The next prime is 247805219. The reversal of 247805213 is 312508742.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 247805213 - 2⁶ = 247805149 is a prime.

It is a super-2 number, since 2×247805213² = 122814847179950738, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 247805213.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (247805219) 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, 323123 + ... + 323888.

It is an arithmetic number, because the mean of its divisors is an integer number (62113152).

Almost surely, 2^247805213 is an apocalyptic number.

It is an amenable number.

247805213 is a deficient number, since it is larger than the sum of its proper divisors (647395).

247805213 is an equidigital number, since it uses as much as digits as its factorization.

247805213 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 647394.

The product of its (nonzero) digits is 13440, while the sum is 32.

The square root of 247805213 is about 15741.8300397381. The cubic root of 247805213 is about 628.1115981167. Note that the first 3 decimals are identical.

The spelling of 247805213 in words is "two hundred forty-seven million, eight hundred five thousand, two hundred thirteen".