12940138 has 4 divisors (see below), whose sum is σ = 19410210. Its totient is φ = 6470068.

The previous prime is 12940129. The next prime is 12940139. The reversal of 12940138 is 83104921.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 83104921 = 101 ⋅822821.

It can be written as a sum of positive squares in only one way, i.e., 7800849 + 5139289 = 2793^2 + 2267^2 .

It is not an unprimeable number, because it can be changed into a prime (12940139) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3235033 + ... + 3235036.

Almost surely, 2^12940138 is an apocalyptic number.

12940138 is a deficient number, since it is larger than the sum of its proper divisors (6470072).

12940138 is an equidigital number, since it uses as much as digits as its factorization.

12940138 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6470071.

The product of its (nonzero) digits is 1728, while the sum is 28.

The square root of 12940138 is about 3597.2403311427. The cubic root of 12940138 is about 234.7720015913.

The spelling of 12940138 in words is "twelve million, nine hundred forty thousand, one hundred thirty-eight".