12912840 has 48 divisors (see below), whose sum is σ = 41967900. Its totient is φ = 3443328.

The previous prime is 12912773. The next prime is 12912847. The reversal of 12912840 is 4821921.

It can be written as a sum of positive squares in 2 ways, for example, as 12574116 + 338724 = 3546^2 + 582^2 .

It is not an unprimeable number, because it can be changed into a prime (12912847) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 17575 + ... + 18294.

Almost surely, 2^12912840 is an apocalyptic number.

12912840 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

12912840 is an abundant number, since it is smaller than the sum of its proper divisors (29055060).

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

12912840 is a wasteful number, since it uses less digits than its factorization.

12912840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35886 (or 35879 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 27.

The square root of 12912840 is about 3593.4440304532. Note that the first 3 decimals coincide. The cubic root of 12912840 is about 234.6067968108.

The spelling of 12912840 in words is "twelve million, nine hundred twelve thousand, eight hundred forty".