12999220 has 72 divisors (see below), whose sum is σ = 31409784. Its totient is φ = 4491264.

The previous prime is 12999193. The next prime is 12999223. The reversal of 12999220 is 2299921.

It can be written as a sum of positive squares in 12 ways, for example, as 197136 + 12802084 = 444^2 + 3578^2 .

It is a Harshad number since it is a multiple of its sum of digits (34).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12999223) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 75054 + ... + 75226.

It is an arithmetic number, because the mean of its divisors is an integer number (436247).

Almost surely, 2^12999220 is an apocalyptic number.

12999220 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 12999220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (15704892).

12999220 is an abundant number, since it is smaller than the sum of its proper divisors (18410564).

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

12999220 is a wasteful number, since it uses less digits than its factorization.

12999220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 229 (or 210 counting only the distinct ones).

The product of its (nonzero) digits is 5832, while the sum is 34.

The square root of 12999220 is about 3605.4431073032. The cubic root of 12999220 is about 235.1287660086.

The spelling of 12999220 in words is "twelve million, nine hundred ninety-nine thousand, two hundred twenty".