161849664 has 98 divisors (see below), whose sum is σ = 481674170. Its totient is φ = 53934336.

The previous prime is 161849663. The next prime is 161849711. The reversal of 161849664 is 466948161.

It can be written as a sum of positive squares in only one way, i.e., 94478400 + 67371264 = 9720^2 + 8208^2 .

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161849663) by changing a digit.

It is a polite number, since it can be written in 13 ways as a sum of consecutive naturals, for example, 44922 + ... + 48390.

Almost surely, 2^161849664 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 161849664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (240837085).

161849664 is an abundant number, since it is smaller than the sum of its proper divisors (319824506).

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

161849664 is an frugal number, since it uses more digits than its factorization.

161849664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3499 (or 3474 counting only the distinct ones).

The product of its digits is 248832, while the sum is 45.

The square root of 161849664 is about 12722.0149347499. The cubic root of 161849664 is about 544.9674968692.

The spelling of 161849664 in words is "one hundred sixty-one million, eight hundred forty-nine thousand, six hundred sixty-four".