12661977 has 4 divisors (see below), whose sum is σ = 16882640. Its totient is φ = 8441316.

The previous prime is 12661973. The next prime is 12661997. The reversal of 12661977 is 77916621.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 77916621 = 3 ⋅25972207.

It is not a de Polignac number, because 12661977 - 2² = 12661973 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (12661973) by changing a digit.

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, 2110327 + ... + 2110332.

It is an arithmetic number, because the mean of its divisors is an integer number (4220660).

Almost surely, 2^12661977 is an apocalyptic number.

It is an amenable number.

12661977 is a deficient number, since it is larger than the sum of its proper divisors (4220663).

12661977 is an equidigital number, since it uses as much as digits as its factorization.

12661977 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4220662.

The product of its digits is 31752, while the sum is 39.

The square root of 12661977 is about 3558.3671817282. The cubic root of 12661977 is about 233.0775835013.

The spelling of 12661977 in words is "twelve million, six hundred sixty-one thousand, nine hundred seventy-seven".