23555220 has 144 divisors (see below), whose sum is σ = 75261312. Its totient is φ = 5491200.

The previous prime is 23555179. The next prime is 23555237. The reversal of 23555220 is 2255532.

23555220 = T₂₈₉ + T₂₉₀ + ... + T₅₄₈.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 233170 + ... + 233270.

It is an arithmetic number, because the mean of its divisors is an integer number (522648).

Almost surely, 2^23555220 is an apocalyptic number.

23555220 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 23555220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37630656).

23555220 is an abundant number, since it is smaller than the sum of its proper divisors (51706092).

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

23555220 is a wasteful number, since it uses less digits than its factorization.

23555220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 162 (or 147 counting only the distinct ones).

The product of its (nonzero) digits is 3000, while the sum is 24.

The square root of 23555220 is about 4853.3720236553. The cubic root of 23555220 is about 286.6568922814.

It can be divided in two parts, 235 and 55220, that added together give a palindrome (55455).

The spelling of 23555220 in words is "twenty-three million, five hundred fifty-five thousand, two hundred twenty".