161020100 has 36 divisors (see below), whose sum is σ = 350735364. Its totient is φ = 64164480.

The previous prime is 161020081. The next prime is 161020103. The reversal of 161020100 is 1020161.

It can be written as a sum of positive squares in 6 ways, for example, as 7706176 + 153313924 = 2776^2 + 12382^2 .

It is not an unprimeable number, because it can be changed into a prime (161020103) 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 11 ways as a sum of consecutive naturals, for example, 24794 + ... + 30606.

It is an arithmetic number, because the mean of its divisors is an integer number (9742649).

Almost surely, 2^161020100 is an apocalyptic number.

161020100 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

161020100 is an abundant number, since it is smaller than the sum of its proper divisors (189715264).

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

161020100 is a wasteful number, since it uses less digits than its factorization.

161020100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6104 (or 6097 counting only the distinct ones).

The product of its (nonzero) digits is 12, while the sum is 11.

The square root of 161020100 is about 12689.3695666885. The cubic root of 161020100 is about 544.0348206157.

Adding to 161020100 its reverse (1020161), we get a palindrome (162040261).

It can be divided in two parts, 16 and 1020100, that multiplied together give a square (16321600 = 4040²).

The spelling of 161020100 in words is "one hundred sixty-one million, twenty thousand, one hundred".