209113969 has 2 divisors, whose sum is σ = 209113970. Its totient is φ = 209113968.

The previous prime is 209113967. The next prime is 209113979. The reversal of 209113969 is 969311902.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 197121600 + 11992369 = 14040^2 + 3463^2 .

It is a cyclic number.

It is not a de Polignac number, because 209113969 - 2¹ = 209113967 is a prime.

It is a super-2 number, since 2×209113969² = 87457304061865922, which contains 22 as substring.

Together with 209113967, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (209113967) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 104556984 + 104556985.

It is an arithmetic number, because the mean of its divisors is an integer number (104556985).

Almost surely, 2^209113969 is an apocalyptic number.

It is an amenable number.

209113969 is a deficient number, since it is larger than the sum of its proper divisors (1).

209113969 is an equidigital number, since it uses as much as digits as its factorization.

209113969 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 26244, while the sum is 40.

The square root of 209113969 is about 14460.7734578756. The cubic root of 209113969 is about 593.5550645909. Note that the first 3 decimals are identical.

The spelling of 209113969 in words is "two hundred nine million, one hundred thirteen thousand, nine hundred sixty-nine".