161432405 has 8 divisors (see below), whose sum is σ = 194566200. Its totient is φ = 128581056.

The previous prime is 161432389. The next prime is 161432431. The reversal of 161432405 is 504234161.

It can be written as a sum of positive squares in 4 ways, for example, as 43970161 + 117462244 = 6631^2 + 10838^2 .

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 161432405 - 2⁴ = 161432389 is a prime.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 69350 + ... + 71639.

It is an arithmetic number, because the mean of its divisors is an integer number (24320775).

Almost surely, 2^161432405 is an apocalyptic number.

It is an amenable number.

161432405 is a deficient number, since it is larger than the sum of its proper divisors (33133795).

161432405 is a wasteful number, since it uses less digits than its factorization.

161432405 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 141223.

The product of its (nonzero) digits is 2880, while the sum is 26.

The square root of 161432405 is about 12705.6052590973. The cubic root of 161432405 is about 544.4987732432.

Adding to 161432405 its reverse (504234161), we get a palindrome (665666566).

The spelling of 161432405 in words is "one hundred sixty-one million, four hundred thirty-two thousand, four hundred five".