12820890 has 64 divisors (see below), whose sum is σ = 34027776. Its totient is φ = 3075072.

The previous prime is 12820889. The next prime is 12820891. The reversal of 12820890 is 9802821.

It is an interprime number because it is at equal distance from previous prime (12820889) and next prime (12820891).

It is a Harshad number since it is a multiple of its sum of digits (30).

It is not an unprimeable number, because it can be changed into a prime (12820891) 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 31 ways as a sum of consecutive naturals, for example, 11184 + ... + 12276.

It is an arithmetic number, because the mean of its divisors is an integer number (531684).

Almost surely, 2^12820890 is an apocalyptic number.

12820890 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 12820890, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (17013888).

12820890 is an abundant number, since it is smaller than the sum of its proper divisors (21206886).

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

12820890 is a wasteful number, since it uses less digits than its factorization.

12820890 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1143.

The product of its (nonzero) digits is 2304, while the sum is 30.

The square root of 12820890 is about 3580.6270400588. The cubic root of 12820890 is about 234.0486055800.

The spelling of 12820890 in words is "twelve million, eight hundred twenty thousand, eight hundred ninety".