161321705 has 8 divisors (see below), whose sum is σ = 195918912. Its totient is φ = 127502128.

The previous prime is 161321683. The next prime is 161321707. The reversal of 161321705 is 507123161.

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 161321705 - 2¹⁰ = 161320681 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 (161321707) 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, 193949 + ... + 194778.

It is an arithmetic number, because the mean of its divisors is an integer number (24489864).

Almost surely, 2^161321705 is an apocalyptic number.

It is an amenable number.

161321705 is a deficient number, since it is larger than the sum of its proper divisors (34597207).

161321705 is an equidigital number, since it uses as much as digits as its factorization.

161321705 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 388815.

The product of its (nonzero) digits is 1260, while the sum is 26.

The square root of 161321705 is about 12701.2481670110. The cubic root of 161321705 is about 544.3742839928.

Adding to 161321705 its reverse (507123161), we get a palindrome (668444866).

The spelling of 161321705 in words is "one hundred sixty-one million, three hundred twenty-one thousand, seven hundred five".