209123961 has 8 divisors (see below), whose sum is σ = 280373184. Its totient is φ = 138645360.

The previous prime is 209123933. The next prime is 209123969. The reversal of 209123961 is 169321902.

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

It is a de Polignac number, because none of the positive numbers 2^k-209123961 is a prime.

It is not an unprimeable number, because it can be changed into a prime (209123969) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 192021 + ... + 193106.

It is an arithmetic number, because the mean of its divisors is an integer number (35046648).

Almost surely, 2^209123961 is an apocalyptic number.

It is an amenable number.

209123961 is a deficient number, since it is larger than the sum of its proper divisors (71249223).

209123961 is a wasteful number, since it uses less digits than its factorization.

209123961 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 385311.

The product of its (nonzero) digits is 5832, while the sum is 33.

The square root of 209123961 is about 14461.1189401097. The cubic root of 209123961 is about 593.5645182997.

The spelling of 209123961 in words is "two hundred nine million, one hundred twenty-three thousand, nine hundred sixty-one".