215555555567 has 4 divisors (see below), whose sum is σ = 235151515176. Its totient is φ = 195959595960.

The previous prime is 215555555533. The next prime is 215555555581. The reversal of 215555555567 is 765555555512.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-215555555567 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 (215555555167) 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, 9797979788 + ... + 9797979809.

It is an arithmetic number, because the mean of its divisors is an integer number (58787878794).

Almost surely, 2^215555555567 is an apocalyptic number.

215555555567 is a deficient number, since it is larger than the sum of its proper divisors (19595959609).

215555555567 is a wasteful number, since it uses less digits than its factorization.

215555555567 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19595959608.

The product of its digits is 32812500, while the sum is 56.

Subtracting 215555555567 from its reverse (765555555512), we obtain a palindrome (549999999945).

It can be divided in two parts, 2155555 and 55567, that added together give a palindrome (2211122).

The spelling of 215555555567 in words is "two hundred fifteen billion, five hundred fifty-five million, five hundred fifty-five thousand, five hundred sixty-seven".