209454129 has 6 divisors (see below), whose sum is σ = 302544866. Its totient is φ = 139636080.

The previous prime is 209454121. The next prime is 209454139. The reversal of 209454129 is 921454902.

209454129 is a `hidden beast` number, since 2 + 0 + 94 + 541 + 29 = 666.

It can be written as a sum of positive squares in only one way, i.e., 108993600 + 100460529 = 10440^2 + 10023^2 .

It is not a de Polignac number, because 209454129 - 2³ = 209454121 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 209454093 and 209454102.

It is not an unprimeable number, because it can be changed into a prime (209454121) 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 5 ways as a sum of consecutive naturals, for example, 11636332 + ... + 11636349.

Almost surely, 2^209454129 is an apocalyptic number.

It is an amenable number.

209454129 is a deficient number, since it is larger than the sum of its proper divisors (93090737).

209454129 is a wasteful number, since it uses less digits than its factorization.

209454129 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23272687 (or 23272684 counting only the distinct ones).

The product of its (nonzero) digits is 25920, while the sum is 36.

The square root of 209454129 is about 14472.5301519810. The cubic root of 209454129 is about 593.8767301934.

The spelling of 209454129 in words is "two hundred nine million, four hundred fifty-four thousand, one hundred twenty-nine".