161633501 has 16 divisors (see below), whose sum is σ = 181848240. Its totient is φ = 142894080.

The previous prime is 161633497. The next prime is 161633519. The reversal of 161633501 is 105336161.

161633501 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 8 ways, for example, as 71402500 + 90231001 = 8450^2 + 9499^2 .

It is a cyclic number.

It is not a de Polignac number, because 161633501 - 2² = 161633497 is a prime.

It is a super-2 number, since 2×161633501² = 52250777291034002, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161633531) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 13811 + ... + 22671.

It is an arithmetic number, because the mean of its divisors is an integer number (11365515).

Almost surely, 2^161633501 is an apocalyptic number.

It is an amenable number.

161633501 is a deficient number, since it is larger than the sum of its proper divisors (20214739).

161633501 is a wasteful number, since it uses less digits than its factorization.

161633501 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8944.

The product of its (nonzero) digits is 1620, while the sum is 26.

The square root of 161633501 is about 12713.5164687037. The cubic root of 161633501 is about 544.7247730773.

Adding to 161633501 its reverse (105336161), we get a palindrome (266969662).

The spelling of 161633501 in words is "one hundred sixty-one million, six hundred thirty-three thousand, five hundred one".