12880920 has 128 divisors (see below), whose sum is σ = 43545600. Its totient is φ = 3024384.

The previous prime is 12880919. The next prime is 12880927. The reversal of 12880920 is 2908821.

12880920 = 138² + 139² + ... + 345².

It is a Cunningham number, because it is equal to 3589²-1.

It is a super-3 number, since 3×12880920³ (a number of 22 digits) contains 333 as substring.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12880927) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 35701 + ... + 36059.

It is an arithmetic number, because the mean of its divisors is an integer number (340200).

Almost surely, 2^12880920 is an apocalyptic number.

12880920 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 12880920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21772800).

12880920 is an abundant number, since it is smaller than the sum of its proper divisors (30664680).

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

12880920 is a wasteful number, since it uses less digits than its factorization.

12880920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 409 (or 405 counting only the distinct ones).

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

The square root of 12880920 is about 3588.9998606854. Note that the first 3 decimals coincide. The cubic root of 12880920 is about 234.4133245773.

The spelling of 12880920 in words is "twelve million, eight hundred eighty thousand, nine hundred twenty".