161665448 has 48 divisors (see below), whose sum is σ = 351126240. Its totient is φ = 68356800.

The previous prime is 161665429. The next prime is 161665481. The reversal of 161665448 is 844566161.

161665448 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×161665448² = 52271434154081408, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 571115 + ... + 571397.

It is an arithmetic number, because the mean of its divisors is an integer number (7315130).

Almost surely, 2^161665448 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 161665448, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (175563120).

161665448 is an abundant number, since it is smaller than the sum of its proper divisors (189460792).

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

161665448 is a wasteful number, since it uses less digits than its factorization.

161665448 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 498 (or 393 counting only the distinct ones).

The product of its digits is 138240, while the sum is 41.

The square root of 161665448 is about 12714.7728253398. The cubic root of 161665448 is about 544.7606591525.

The spelling of 161665448 in words is "one hundred sixty-one million, six hundred sixty-five thousand, four hundred forty-eight".