21523303511 has 4 divisors (see below), whose sum is σ = 21526165224. Its totient is φ = 21520441800.

The previous prime is 21523303489. The next prime is 21523303513. The reversal of 21523303511 is 11530332512.

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 21523303511 - 2¹⁰ = 21523302487 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 (21523303513) 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, 1419545 + ... + 1434626.

It is an arithmetic number, because the mean of its divisors is an integer number (5381541306).

Almost surely, 2^21523303511 is an apocalyptic number.

21523303511 is a deficient number, since it is larger than the sum of its proper divisors (2861713).

21523303511 is an equidigital number, since it uses as much as digits as its factorization.

21523303511 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2861712.

The product of its (nonzero) digits is 2700, while the sum is 26.

The spelling of 21523303511 in words is "twenty-one billion, five hundred twenty-three million, three hundred three thousand, five hundred eleven".