209920969 has 8 divisors (see below), whose sum is σ = 218858112. Its totient is φ = 201168240.

The previous prime is 209920961. The next prime is 209920973. The reversal of 209920969 is 969029902.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 209920969 - 2³ = 209920961 is a prime.

It is a super-2 number, since 2×209920969² = 88133626451797922, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (209920961) 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, 43777 + ... + 48334.

It is an arithmetic number, because the mean of its divisors is an integer number (27357264).

Almost surely, 2^209920969 is an apocalyptic number.

It is an amenable number.

209920969 is a deficient number, since it is larger than the sum of its proper divisors (8937143).

209920969 is an equidigital number, since it uses as much as digits as its factorization.

209920969 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 92207.

The product of its (nonzero) digits is 157464, while the sum is 46.

The square root of 209920969 is about 14488.6496610278. The cubic root of 209920969 is about 594.3176217784.

The spelling of 209920969 in words is "two hundred nine million, nine hundred twenty thousand, nine hundred sixty-nine".