23217240 has 128 divisors (see below), whose sum is σ = 77760000. Its totient is φ = 5511168.

The previous prime is 23217211. The next prime is 23217247. The reversal of 23217240 is 4271232.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (23217247) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 38461 + ... + 39059.

It is an arithmetic number, because the mean of its divisors is an integer number (607500).

Almost surely, 2^23217240 is an apocalyptic number.

23217240 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 23217240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (38880000).

23217240 is an abundant number, since it is smaller than the sum of its proper divisors (54542760).

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

23217240 is a wasteful number, since it uses less digits than its factorization.

23217240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 649 (or 645 counting only the distinct ones).

The product of its (nonzero) digits is 672, while the sum is 21.

The square root of 23217240 is about 4818.4271292612. The cubic root of 23217240 is about 285.2792584418.

Adding to 23217240 its reverse (4271232), we get a palindrome (27488472).

The spelling of 23217240 in words is "twenty-three million, two hundred seventeen thousand, two hundred forty".