12920040 has 128 divisors (see below), whose sum is σ = 49248000. Its totient is φ = 2951424.

The previous prime is 12920023. The next prime is 12920071. The reversal of 12920040 is 4002921.

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 = 12919995 and 12920022.

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, 6706 + ... + 8414.

It is an arithmetic number, because the mean of its divisors is an integer number (384750).

Almost surely, 2^12920040 is an apocalyptic number.

12920040 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 12920040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24624000).

12920040 is an abundant number, since it is smaller than the sum of its proper divisors (36327960).

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

12920040 is a wasteful number, since it uses less digits than its factorization.

12920040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1736 (or 1726 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 18.

The square root of 12920040 is about 3594.4457152668. The cubic root of 12920040 is about 234.6503930835.

Adding to 12920040 its reverse (4002921), we get a palindrome (16922961).

The spelling of 12920040 in words is "twelve million, nine hundred twenty thousand, forty".