161131012 has 36 divisors (see below), whose sum is σ = 333418764. Its totient is φ = 67919040.

The previous prime is 161130997. The next prime is 161131063. The reversal of 161131012 is 210131161.

It can be written as a sum of positive squares in 2 ways, for example, as 48219136 + 112911876 = 6944^2 + 10626^2 .

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 11 ways as a sum of consecutive naturals, for example, 5218 + ... + 18694.

Almost surely, 2^161131012 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 161131012, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (166709382).

161131012 is an abundant number, since it is smaller than the sum of its proper divisors (172287752).

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

161131012 is a wasteful number, since it uses less digits than its factorization.

161131012 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13556 (or 13547 counting only the distinct ones).

The product of its (nonzero) digits is 36, while the sum is 16.

The square root of 161131012 is about 12693.7390866521. The cubic root of 161131012 is about 544.1597038675.

Adding to 161131012 its reverse (210131161), we get a palindrome (371262173).

It can be divided in two parts, 1611 and 31012, that added together give a palindrome (32623).

The spelling of 161131012 in words is "one hundred sixty-one million, one hundred thirty-one thousand, twelve".