161655121155 has 64 divisors (see below), whose sum is σ = 283576204800. Its totient is φ = 77986360320.

The previous prime is 161655121139. The next prime is 161655121169. The reversal of 161655121155 is 551121556161.

It is not a de Polignac number, because 161655121155 - 2⁴ = 161655121139 is a prime.

It is a super-2 number, since 2×161655121155² (a number of 23 digits) contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 28273357 + ... + 28279073.

It is an arithmetic number, because the mean of its divisors is an integer number (4430878200).

Almost surely, 2^161655121155 is an apocalyptic number.

161655121155 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

161655121155 is a deficient number, since it is larger than the sum of its proper divisors (121921083645).

161655121155 is a wasteful number, since it uses less digits than its factorization.

161655121155 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6564.

The product of its digits is 45000, while the sum is 39.

The spelling of 161655121155 in words is "one hundred sixty-one billion, six hundred fifty-five million, one hundred twenty-one thousand, one hundred fifty-five".