1255661605641 has 4 divisors (see below), whose sum is σ = 1674215474192. Its totient is φ = 837107737092.

The previous prime is 1255661605637. The next prime is 1255661605643. The reversal of 1255661605641 is 1465061665521.

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.

It is not a de Polignac number, because 1255661605641 - 2² = 1255661605637 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1255661605643) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 209276934271 + ... + 209276934276.

It is an arithmetic number, because the mean of its divisors is an integer number (418553868548).

Almost surely, 2^{1255661605641} is an apocalyptic number.

It is an amenable number.

1255661605641 is a deficient number, since it is larger than the sum of its proper divisors (418553868551).

1255661605641 is an equidigital number, since it uses as much as digits as its factorization.

1255661605641 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 418553868550.

The product of its (nonzero) digits is 1296000, while the sum is 48.

The spelling of 1255661605641 in words is "one trillion, two hundred fifty-five billion, six hundred sixty-one million, six hundred five thousand, six hundred forty-one".