21564363240435 has 128 divisors (see below), whose sum is σ = 36682383209472. Its totient is φ = 10804147200000.

The previous prime is 21564363240359. The next prime is 21564363240437. The reversal of 21564363240435 is 53404236346512.

It is not a de Polignac number, because 21564363240435 - 2¹¹ = 21564363238387 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21564363240437) by changing a digit.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 622312860 + ... + 622347510.

It is an arithmetic number, because the mean of its divisors is an integer number (286581118824).

Almost surely, 2^{21564363240435} is an apocalyptic number.

21564363240435 is a deficient number, since it is larger than the sum of its proper divisors (15118019969037).

21564363240435 is a wasteful number, since it uses less digits than its factorization.

21564363240435 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 35077.

The product of its (nonzero) digits is 6220800, while the sum is 48.

Adding to 21564363240435 its reverse (53404236346512), we get a palindrome (74968599586947).

The spelling of 21564363240435 in words is "twenty-one trillion, five hundred sixty-four billion, three hundred sixty-three million, two hundred forty thousand, four hundred thirty-five".