161061220 has 12 divisors (see below), whose sum is σ = 338228604. Its totient is φ = 64424480.

The previous prime is 161061217. The next prime is 161061227. The reversal of 161061220 is 22160161.

It can be written as a sum of positive squares in 2 ways, for example, as 49674304 + 111386916 = 7048^2 + 10554^2 .

It is a nialpdrome in base 16.

It is not an unprimeable number, because it can be changed into a prime (161061227) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4026511 + ... + 4026550.

It is an arithmetic number, because the mean of its divisors is an integer number (28185717).

Almost surely, 2^161061220 is an apocalyptic number.

161061220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

161061220 is an abundant number, since it is smaller than the sum of its proper divisors (177167384).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

161061220 is a wasteful number, since it uses less digits than its factorization.

161061220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8053070 (or 8053068 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 19.

The square root of 161061220 is about 12690.9897171182. The cubic root of 161061220 is about 544.0811270661.

The spelling of 161061220 in words is "one hundred sixty-one million, sixty-one thousand, two hundred twenty".