11564353421 has 4 divisors (see below), whose sum is σ = 11565248700. Its totient is φ = 11563458144.

The previous prime is 11564353349. The next prime is 11564353447. The reversal of 11564353421 is 12435346511.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 12435346511 = 7 ⋅1776478073.

It can be written as a sum of positive squares in 2 ways, for example, as 6996486025 + 4567867396 = 83645^2 + 67586^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-11564353421 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 (11564353121) 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, 427976 + ... + 454193.

It is an arithmetic number, because the mean of its divisors is an integer number (2891312175).

Almost surely, 2^11564353421 is an apocalyptic number.

It is an amenable number.

11564353421 is a deficient number, since it is larger than the sum of its proper divisors (895279).

11564353421 is an equidigital number, since it uses as much as digits as its factorization.

11564353421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 895278.

The product of its digits is 43200, while the sum is 35.

Adding to 11564353421 its reverse (12435346511), we get a palindrome (23999699932).

The spelling of 11564353421 in words is "eleven billion, five hundred sixty-four million, three hundred fifty-three thousand, four hundred twenty-one".