23161320 has 288 divisors, whose sum is σ = 95233320. Its totient is φ = 4838400.

The previous prime is 23161319. The next prime is 23161331. The reversal of 23161320 is 2316132.

23161320 is a `hidden beast` number, since 2 + 31 + 613 + 20 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 20196036 + 2965284 = 4494^2 + 1722^2 .

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 23161293 and 23161302.

It is an unprimeable number.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 229270 + ... + 229370.

Almost surely, 2^23161320 is an apocalyptic number.

23161320 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 23161320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (47616660).

23161320 is an abundant number, since it is smaller than the sum of its proper divisors (72072000).

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

23161320 is a wasteful number, since it uses less digits than its factorization.

23161320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 145 (or 131 counting only the distinct ones).

The product of its (nonzero) digits is 216, while the sum is 18.

The square root of 23161320 is about 4812.6209075721. The cubic root of 23161320 is about 285.0500373825.

Adding to 23161320 its reverse (2316132), we get a palindrome (25477452).

The spelling of 23161320 in words is "twenty-three million, one hundred sixty-one thousand, three hundred twenty".