12978220 has 12 divisors (see below), whose sum is σ = 27254304. Its totient is φ = 5191280.

The previous prime is 12978211. The next prime is 12978227. The reversal of 12978220 is 2287921.

It is not an unprimeable number, because it can be changed into a prime (12978227) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 324436 + ... + 324475.

It is an arithmetic number, because the mean of its divisors is an integer number (2271192).

Almost surely, 2^12978220 is an apocalyptic number.

12978220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

12978220 is an abundant number, since it is smaller than the sum of its proper divisors (14276084).

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

12978220 is a wasteful number, since it uses less digits than its factorization.

12978220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 648920 (or 648918 counting only the distinct ones).

The product of its (nonzero) digits is 4032, while the sum is 31.

The square root of 12978220 is about 3602.5296667758. The cubic root of 12978220 is about 235.0020823718.

The spelling of 12978220 in words is "twelve million, nine hundred seventy-eight thousand, two hundred twenty".