209053993 has 2 divisors, whose sum is σ = 209053994. Its totient is φ = 209053992.

The previous prime is 209053991. The next prime is 209054023. The reversal of 209053993 is 399350902.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 172475689 + 36578304 = 13133^2 + 6048^2 .

It is a cyclic number.

It is not a de Polignac number, because 209053993 - 2¹ = 209053991 is a prime.

Together with 209053991, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (209053991) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 104526996 + 104526997.

It is an arithmetic number, because the mean of its divisors is an integer number (104526997).

Almost surely, 2^209053993 is an apocalyptic number.

209053993 is the 7729-th centered heptagonal number.

It is an amenable number.

209053993 is a deficient number, since it is larger than the sum of its proper divisors (1).

209053993 is an equidigital number, since it uses as much as digits as its factorization.

209053993 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 65610, while the sum is 40.

The square root of 209053993 is about 14458.6995611639. The cubic root of 209053993 is about 593.4983133009.

The spelling of 209053993 in words is "two hundred nine million, fifty-three thousand, nine hundred ninety-three".