12881920 has 104 divisors (see below), whose sum is σ = 33615864. Its totient is φ = 4718592.

The previous prime is 12881917. The next prime is 12881923. The reversal of 12881920 is 2918821.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (12881917) and next prime (12881923).

It can be written as a sum of positive squares in 4 ways, for example, as 5308416 + 7573504 = 2304^2 + 2752^2 .

It is a nialpdrome in base 8.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12881923) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 348142 + ... + 348178.

Almost surely, 2^12881920 is an apocalyptic number.

12881920 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 12881920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (16807932).

12881920 is an abundant number, since it is smaller than the sum of its proper divisors (20733944).

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

12881920 is an equidigital number, since it uses as much as digits as its factorization.

12881920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 83 (or 61 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 31.

The square root of 12881920 is about 3589.1391725593. The cubic root of 12881920 is about 234.4193905845.

The spelling of 12881920 in words is "twelve million, eight hundred eighty-one thousand, nine hundred twenty".