21346211545 has 4 divisors (see below), whose sum is σ = 25615453860. Its totient is φ = 17076969232.

The previous prime is 21346211543. The next prime is 21346211597. The reversal of 21346211545 is 54511264312.

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

It can be written as a sum of positive squares in 2 ways, for example, as 4474539664 + 16871671881 = 66892^2 + 129891^2 .

It is a cyclic number.

It is not a de Polignac number, because 21346211545 - 2¹ = 21346211543 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21346211545.

It is not an unprimeable number, because it can be changed into a prime (21346211543) 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 3 ways as a sum of consecutive naturals, for example, 2134621150 + ... + 2134621159.

It is an arithmetic number, because the mean of its divisors is an integer number (6403863465).

Almost surely, 2^21346211545 is an apocalyptic number.

It is an amenable number.

21346211545 is a deficient number, since it is larger than the sum of its proper divisors (4269242315).

21346211545 is an equidigital number, since it uses as much as digits as its factorization.

21346211545 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4269242314.

The product of its digits is 28800, while the sum is 34.

Adding to 21346211545 its reverse (54511264312), we get a palindrome (75857475857).

The spelling of 21346211545 in words is "twenty-one billion, three hundred forty-six million, two hundred eleven thousand, five hundred forty-five".