209157 has 16 divisors (see below), whose sum is σ = 311808. Its totient is φ = 123840.

The previous prime is 209147. The next prime is 209159. The reversal of 209157 is 751902.

It is not a de Polignac number, because 209157 - 2⁷ = 209029 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (209159) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1123 + ... + 1295.

It is an arithmetic number, because the mean of its divisors is an integer number (19488).

2²⁰⁹¹⁵⁷ is an apocalyptic number.

It is an amenable number.

209157 is a deficient number, since it is larger than the sum of its proper divisors (102651).

209157 is a wasteful number, since it uses less digits than its factorization.

209157 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 220.

The product of its (nonzero) digits is 630, while the sum is 24.

The square root of 209157 is about 457.3368561575. The cubic root of 209157 is about 59.3595775272.

The spelling of 209157 in words is "two hundred nine thousand, one hundred fifty-seven".