21153340423 has 8 divisors (see below), whose sum is σ = 21227477040. Its totient is φ = 21079238400.

The previous prime is 21153340421. The next prime is 21153340441. The reversal of 21153340423 is 32404335112.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21153340423 - 2¹ = 21153340421 is a prime.

It is a super-2 number, since 2×21153340423² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21153340391 and 21153340400.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21153340421) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2048373 + ... + 2058673.

It is an arithmetic number, because the mean of its divisors is an integer number (2653434630).

Almost surely, 2^21153340423 is an apocalyptic number.

21153340423 is a deficient number, since it is larger than the sum of its proper divisors (74136617).

21153340423 is a wasteful number, since it uses less digits than its factorization.

21153340423 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17297.

The product of its (nonzero) digits is 8640, while the sum is 28.

Adding to 21153340423 its reverse (32404335112), we get a palindrome (53557675535).

The spelling of 21153340423 in words is "twenty-one billion, one hundred fifty-three million, three hundred forty thousand, four hundred twenty-three".