209908131 has 8 divisors (see below), whose sum is σ = 280151040. Its totient is φ = 139801992.

The previous prime is 209908123. The next prime is 209908133. The reversal of 209908131 is 131809902.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 209908131 - 2³ = 209908123 is a prime.

It is a super-2 number, since 2×209908131² = 88122846919826322, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 209908092 and 209908101.

It is not an unprimeable number, because it can be changed into a prime (209908133) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 30555 + ... + 36788.

It is an arithmetic number, because the mean of its divisors is an integer number (35018880).

Almost surely, 2^209908131 is an apocalyptic number.

209908131 is a deficient number, since it is larger than the sum of its proper divisors (70242909).

209908131 is a wasteful number, since it uses less digits than its factorization.

209908131 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 68385.

The product of its (nonzero) digits is 3888, while the sum is 33.

The square root of 209908131 is about 14488.2066177978. The cubic root of 209908131 is about 594.3055060995.

The spelling of 209908131 in words is "two hundred nine million, nine hundred eight thousand, one hundred thirty-one".