209400257 has 16 divisors (see below), whose sum is σ = 246067200. Its totient is φ = 176206800.

The previous prime is 209400223. The next prime is 209400277. The reversal of 209400257 is 752004902.

209400257 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 209400257 - 2⁶ = 209400193 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (209400277) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5507 + ... + 21192.

It is an arithmetic number, because the mean of its divisors is an integer number (15379200).

Almost surely, 2^209400257 is an apocalyptic number.

It is an amenable number.

209400257 is a deficient number, since it is larger than the sum of its proper divisors (36666943).

209400257 is a wasteful number, since it uses less digits than its factorization.

209400257 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26764.

The product of its (nonzero) digits is 5040, while the sum is 29.

The square root of 209400257 is about 14470.6688511623. The cubic root of 209400257 is about 593.8258104198.

The spelling of 209400257 in words is "two hundred nine million, four hundred thousand, two hundred fifty-seven".