161213009 has 8 divisors (see below), whose sum is σ = 163618560. Its totient is φ = 158816736.

The previous prime is 161212999. The next prime is 161213029. The reversal of 161213009 is 900312161.

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 161213009 - 2⁴ = 161212993 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (161213029) 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, 37709 + ... + 41765.

It is an arithmetic number, because the mean of its divisors is an integer number (20452320).

Almost surely, 2^161213009 is an apocalyptic number.

It is an amenable number.

161213009 is a deficient number, since it is larger than the sum of its proper divisors (2405551).

161213009 is an equidigital number, since it uses as much as digits as its factorization.

161213009 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4639.

The product of its (nonzero) digits is 324, while the sum is 23.

The square root of 161213009 is about 12696.9684964562. The cubic root of 161213009 is about 544.2519929436.

The spelling of 161213009 in words is "one hundred sixty-one million, two hundred thirteen thousand, nine".