12551220 has 96 divisors (see below), whose sum is σ = 42618240. Its totient is φ = 3041280.

The previous prime is 12551213. The next prime is 12551239. The reversal of 12551220 is 2215521.

12551220 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 = 12551193 and 12551202.

It is a congruent number.

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, 4884 + ... + 6996.

It is an arithmetic number, because the mean of its divisors is an integer number (443940).

Almost surely, 2^12551220 is an apocalyptic number.

12551220 is a gapful number since it is divisible by the number (10) 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 12551220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21309120).

12551220 is an abundant number, since it is smaller than the sum of its proper divisors (30067020).

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

12551220 is a wasteful number, since it uses less digits than its factorization.

12551220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2142 (or 2134 counting only the distinct ones).

The product of its (nonzero) digits is 200, while the sum is 18.

The square root of 12551220 is about 3542.7701026174. The cubic root of 12551220 is about 232.3959992715.

Adding to 12551220 its reverse (2215521), we get a palindrome (14766741).

The spelling of 12551220 in words is "twelve million, five hundred fifty-one thousand, two hundred twenty".