12955781 has 4 divisors (see below), whose sum is σ = 12963552. Its totient is φ = 12948012.

The previous prime is 12955759. The next prime is 12955783. The reversal of 12955781 is 18755921.

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 a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 18755921 = 163 ⋅115067.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-12955781 is a prime.

It is a super-2 number, since 2×12955781² = 335704522639922, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12955783) 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, 251 + ... + 5096.

It is an arithmetic number, because the mean of its divisors is an integer number (3240888).

Almost surely, 2^12955781 is an apocalyptic number.

It is an amenable number.

12955781 is a deficient number, since it is larger than the sum of its proper divisors (7771).

12955781 is an equidigital number, since it uses as much as digits as its factorization.

12955781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7770.

The product of its digits is 25200, while the sum is 38.

The square root of 12955781 is about 3599.4139800806. The cubic root of 12955781 is about 234.8665667738.

The spelling of 12955781 in words is "twelve million, nine hundred fifty-five thousand, seven hundred eighty-one".