21203327623 has 4 divisors (see below), whose sum is σ = 21205911888. Its totient is φ = 21200743360.

The previous prime is 21203327617. The next prime is 21203327627. The reversal of 21203327623 is 32672330212.

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 21203327623 - 2⁹ = 21203327111 is a prime.

It is a super-2 number, since 2×21203327623² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21203327627) 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, 1279786 + ... + 1296247.

It is an arithmetic number, because the mean of its divisors is an integer number (5301477972).

Almost surely, 2^21203327623 is an apocalyptic number.

21203327623 is a deficient number, since it is larger than the sum of its proper divisors (2584265).

21203327623 is an equidigital number, since it uses as much as digits as its factorization.

21203327623 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2584264.

The product of its (nonzero) digits is 18144, while the sum is 31.

Adding to 21203327623 its reverse (32672330212), we get a palindrome (53875657835).

The spelling of 21203327623 in words is "twenty-one billion, two hundred three million, three hundred twenty-seven thousand, six hundred twenty-three".