12721955 has 4 divisors (see below), whose sum is σ = 15266352. Its totient is φ = 10177560.

The previous prime is 12721939. The next prime is 12721999. The reversal of 12721955 is 55912721.

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: 55912721 = 53 ⋅1054957.

It is not a de Polignac number, because 12721955 - 2⁴ = 12721939 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1272191 + ... + 1272200.

It is an arithmetic number, because the mean of its divisors is an integer number (3816588).

Almost surely, 2^12721955 is an apocalyptic number.

12721955 is a deficient number, since it is larger than the sum of its proper divisors (2544397).

12721955 is an equidigital number, since it uses as much as digits as its factorization.

12721955 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2544396.

The product of its digits is 6300, while the sum is 32.

The square root of 12721955 is about 3566.7849668854. The cubic root of 12721955 is about 233.4450224932.

The spelling of 12721955 in words is "twelve million, seven hundred twenty-one thousand, nine hundred fifty-five".