215540440242 has 64 divisors (see below), whose sum is σ = 462194812800. Its totient is φ = 66768666624.

The previous prime is 215540440231. The next prime is 215540440249. The reversal of 215540440242 is 242044045512.

215540440242 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not an unprimeable number, because it can be changed into a prime (215540440249) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 17882634 + ... + 17894682.

It is an arithmetic number, because the mean of its divisors is an integer number (7221793950).

Almost surely, 2^215540440242 is an apocalyptic number.

215540440242 is an abundant number, since it is smaller than the sum of its proper divisors (246654372558).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

215540440242 is a wasteful number, since it uses less digits than its factorization.

215540440242 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14267.

The product of its (nonzero) digits is 51200, while the sum is 33.

Adding to 215540440242 its reverse (242044045512), we get a palindrome (457584485754).

The spelling of 215540440242 in words is "two hundred fifteen billion, five hundred forty million, four hundred forty thousand, two hundred forty-two".