161555605 has 8 divisors (see below), whose sum is σ = 194083200. Its totient is φ = 129100176.

The previous prime is 161555587. The next prime is 161555623. The reversal of 161555605 is 506555161.

It is an interprime number because it is at equal distance from previous prime (161555587) and next prime (161555623).

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 161555605 - 2²³ = 153166997 is a prime.

It is a super-2 number, since 2×161555605² = 52200427013832050, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 12985 + ... + 22174.

It is an arithmetic number, because the mean of its divisors is an integer number (24260400).

Almost surely, 2^161555605 is an apocalyptic number.

It is an amenable number.

161555605 is a deficient number, since it is larger than the sum of its proper divisors (32527595).

161555605 is an equidigital number, since it uses as much as digits as its factorization.

161555605 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36083.

The product of its (nonzero) digits is 22500, while the sum is 34.

The square root of 161555605 is about 12710.4525883227. The cubic root of 161555605 is about 544.6372526501.

The spelling of 161555605 in words is "one hundred sixty-one million, five hundred fifty-five thousand, six hundred five".