12918981 has 8 divisors (see below), whose sum is σ = 17392960. Its totient is φ = 8528832.

The previous prime is 12918979. The next prime is 12918991. The reversal of 12918981 is 18981921.

12918981 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 12918981 - 2¹ = 12918979 is a prime.

It is a super-2 number, since 2×12918981² = 333800140156722, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12918901) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 20596 + ... + 21213.

It is an arithmetic number, because the mean of its divisors is an integer number (2174120).

Almost surely, 2^12918981 is an apocalyptic number.

It is an amenable number.

12918981 is a deficient number, since it is larger than the sum of its proper divisors (4473979).

12918981 is a wasteful number, since it uses less digits than its factorization.

12918981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 41915.

The product of its digits is 10368, while the sum is 39.

The square root of 12918981 is about 3594.2984016356. The cubic root of 12918981 is about 234.6439818145.

It can be divided in two parts, 129 and 18981, that added together give a triangular number (19110 = T₁₉₅).

The spelling of 12918981 in words is "twelve million, nine hundred eighteen thousand, nine hundred eighty-one".