23138220 has 96 divisors (see below), whose sum is σ = 74995200. Its totient is φ = 5220864.

The previous prime is 23138197. The next prime is 23138237. The reversal of 23138220 is 2283132.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 37071 + ... + 37689.

It is an arithmetic number, because the mean of its divisors is an integer number (781200).

Almost surely, 2^23138220 is an apocalyptic number.

23138220 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 23138220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37497600).

23138220 is an abundant number, since it is smaller than the sum of its proper divisors (51856980).

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

23138220 is a wasteful number, since it uses less digits than its factorization.

23138220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 727 (or 725 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 21.

The square root of 23138220 is about 4810.2203691723. The cubic root of 23138220 is about 284.9552407395.

The spelling of 23138220 in words is "twenty-three million, one hundred thirty-eight thousand, two hundred twenty".