255511115551 has 4 divisors (see below), whose sum is σ = 266620294512. Its totient is φ = 244401936592.

The previous prime is 255511115539. The next prime is 255511115603. The reversal of 255511115551 is 155511115552.

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

It is a cyclic number.

It is not a de Polignac number, because 255511115551 - 2¹³ = 255511107359 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 255511115551.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (255511115501) 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, 5554589446 + ... + 5554589491.

It is an arithmetic number, because the mean of its divisors is an integer number (66655073628).

Almost surely, 2^255511115551 is an apocalyptic number.

255511115551 is a deficient number, since it is larger than the sum of its proper divisors (11109178961).

255511115551 is a wasteful number, since it uses less digits than its factorization.

255511115551 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11109178960.

The product of its digits is 31250, while the sum is 37.

Subtracting from 255511115551 its reverse (155511115552), we obtain a palindrome (99999999999).

The spelling of 255511115551 in words is "two hundred fifty-five billion, five hundred eleven million, one hundred fifteen thousand, five hundred fifty-one".