209734155 has 12 divisors (see below), whose sum is σ = 363539280. Its totient is φ = 111858192.

The previous prime is 209734139. The next prime is 209734157. The reversal of 209734155 is 551437902.

It is not a de Polignac number, because 209734155 - 2⁴ = 209734139 is a prime.

It is not an unprimeable number, because it can be changed into a prime (209734157) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2330335 + ... + 2330424.

It is an arithmetic number, because the mean of its divisors is an integer number (30294940).

Almost surely, 2^209734155 is an apocalyptic number.

209734155 is a deficient number, since it is larger than the sum of its proper divisors (153805125).

209734155 is a wasteful number, since it uses less digits than its factorization.

209734155 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4660770 (or 4660767 counting only the distinct ones).

The product of its (nonzero) digits is 37800, while the sum is 36.

The square root of 209734155 is about 14482.2013174793. The cubic root of 209734155 is about 594.1412700078.

The spelling of 209734155 in words is "two hundred nine million, seven hundred thirty-four thousand, one hundred fifty-five".