209999893 has 2 divisors, whose sum is σ = 209999894. Its totient is φ = 209999892.

The previous prime is 209999891. The next prime is 209999897. The reversal of 209999893 is 398999902.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 177475684 + 32524209 = 13322^2 + 5703^2 .

It is a cyclic number.

It is not a de Polignac number, because 209999893 - 2¹ = 209999891 is a prime.

It is a super-2 number, since 2×209999893² = 88199910120022898, which contains 22 as substring.

Together with 209999891, it forms a pair of twin primes.

It is a plaindrome in base 13.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (209999891) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 104999946 + 104999947.

It is an arithmetic number, because the mean of its divisors is an integer number (104999947).

Almost surely, 2^209999893 is an apocalyptic number.

It is an amenable number.

209999893 is a deficient number, since it is larger than the sum of its proper divisors (1).

209999893 is an equidigital number, since it uses as much as digits as its factorization.

209999893 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2834352, while the sum is 58.

The square root of 209999893 is about 14491.3730543382. The cubic root of 209999893 is about 594.3920943240.

The spelling of 209999893 in words is "two hundred nine million, nine hundred ninety-nine thousand, eight hundred ninety-three".