21611723065323 has 4 divisors (see below), whose sum is σ = 28815630753768. Its totient is φ = 14407815376880.

The previous prime is 21611723065291. The next prime is 21611723065351. The reversal of 21611723065323 is 32356032711612.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 21611723065323 - 2⁵ = 21611723065291 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21611723067323) 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, 3601953844218 + ... + 3601953844223.

It is an arithmetic number, because the mean of its divisors is an integer number (7203907688442).

Almost surely, 2^{21611723065323} is an apocalyptic number.

21611723065323 is a deficient number, since it is larger than the sum of its proper divisors (7203907688445).

21611723065323 is an equidigital number, since it uses as much as digits as its factorization.

21611723065323 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7203907688444.

The product of its (nonzero) digits is 272160, while the sum is 42.

Adding to 21611723065323 its reverse (32356032711612), we get a palindrome (53967755776935).

The spelling of 21611723065323 in words is "twenty-one trillion, six hundred eleven billion, seven hundred twenty-three million, sixty-five thousand, three hundred twenty-three".