209983257 has 12 divisors (see below), whose sum is σ = 330882864. Its totient is φ = 127262520.

The previous prime is 209983237. The next prime is 209983271. The reversal of 209983257 is 752389902.

It is not a de Polignac number, because 209983257 - 2¹⁰ = 209982233 is a prime.

It is not an unprimeable number, because it can be changed into a prime (209983217) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1060423 + ... + 1060620.

It is an arithmetic number, because the mean of its divisors is an integer number (27573572).

Almost surely, 2^209983257 is an apocalyptic number.

It is an amenable number.

209983257 is a deficient number, since it is larger than the sum of its proper divisors (120899607).

209983257 is a wasteful number, since it uses less digits than its factorization.

209983257 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2121060 (or 2121057 counting only the distinct ones).

The product of its (nonzero) digits is 272160, while the sum is 45.

The square root of 209983257 is about 14490.7990462914. The cubic root of 209983257 is about 594.3763981763.

The spelling of 209983257 in words is "two hundred nine million, nine hundred eighty-three thousand, two hundred fifty-seven".