21242255535 has 32 divisors (see below), whose sum is σ = 37772640000. Its totient is φ = 11326614048.

The previous prime is 21242255533. The next prime is 21242255543. The reversal of 21242255535 is 53555224212.

It is not a de Polignac number, because 21242255535 - 2¹ = 21242255533 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21242255535.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21242255533) 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 31 ways as a sum of consecutive naturals, for example, 672936 + ... + 703794.

It is an arithmetic number, because the mean of its divisors is an integer number (1180395000).

Almost surely, 2^21242255535 is an apocalyptic number.

21242255535 is a deficient number, since it is larger than the sum of its proper divisors (16530384465).

21242255535 is a wasteful number, since it uses less digits than its factorization.

21242255535 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 35972 (or 35966 counting only the distinct ones).

The product of its digits is 120000, while the sum is 36.

Adding to 21242255535 its reverse (53555224212), we get a palindrome (74797479747).

The spelling of 21242255535 in words is "twenty-one billion, two hundred forty-two million, two hundred fifty-five thousand, five hundred thirty-five".