255555101021 has 4 divisors (see below), whose sum is σ = 278787382944. Its totient is φ = 232322819100.

The previous prime is 255555100979. The next prime is 255555101033. The reversal of 255555101021 is 120101555552.

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 a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-255555101021 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (255555101041) 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, 11616140945 + ... + 11616140966.

It is an arithmetic number, because the mean of its divisors is an integer number (69696845736).

Almost surely, 2^255555101021 is an apocalyptic number.

It is an amenable number.

255555101021 is a deficient number, since it is larger than the sum of its proper divisors (23232281923).

255555101021 is a wasteful number, since it uses less digits than its factorization.

255555101021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23232281922.

The product of its (nonzero) digits is 12500, while the sum is 32.

Adding to 255555101021 its reverse (120101555552), we get a palindrome (375656656573).

The spelling of 255555101021 in words is "two hundred fifty-five billion, five hundred fifty-five million, one hundred one thousand, twenty-one".