255403956561 has 16 divisors (see below), whose sum is σ = 366742973184. Its totient is φ = 157167771264.

The previous prime is 255403956559. The next prime is 255403956673. The reversal of 255403956561 is 165659304552.

It is not a de Polignac number, because 255403956561 - 2¹ = 255403956559 is a prime.

It is not an unprimeable number, because it can be changed into a prime (255403956761) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2894680 + ... + 2981606.

It is an arithmetic number, because the mean of its divisors is an integer number (22921435824).

Almost surely, 2^255403956561 is an apocalyptic number.

It is an amenable number.

255403956561 is a deficient number, since it is larger than the sum of its proper divisors (111339016623).

255403956561 is a wasteful number, since it uses less digits than its factorization.

255403956561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 162280.

The product of its (nonzero) digits is 4860000, while the sum is 51.

The spelling of 255403956561 in words is "two hundred fifty-five billion, four hundred three million, nine hundred fifty-six thousand, five hundred sixty-one".