12961555 has 4 divisors (see below), whose sum is σ = 15553872. Its totient is φ = 10369240.

The previous prime is 12961537. The next prime is 12961561. The reversal of 12961555 is 55516921.

12961555 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It is a de Polignac number, because none of the positive numbers 2^k-12961555 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 12961555.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1296151 + ... + 1296160.

It is an arithmetic number, because the mean of its divisors is an integer number (3888468).

Almost surely, 2^12961555 is an apocalyptic number.

12961555 is a deficient number, since it is larger than the sum of its proper divisors (2592317).

12961555 is an equidigital number, since it uses as much as digits as its factorization.

12961555 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2592316.

The product of its digits is 13500, while the sum is 34.

The square root of 12961555 is about 3600.2159657443. The cubic root of 12961555 is about 234.9014525685.

The spelling of 12961555 in words is "twelve million, nine hundred sixty-one thousand, five hundred fifty-five".