21420331123 has 8 divisors (see below), whose sum is σ = 21831282000. Its totient is φ = 21009631968.

The previous prime is 21420331117. The next prime is 21420331159. The reversal of 21420331123 is 32113302412.

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 21420331123 - 2⁹ = 21420330611 is a prime.

It is a super-3 number, since 3×21420331123³ (a number of 32 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21420331094 and 21420331103.

It is not an unprimeable number, because it can be changed into a prime (21420334123) 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, 113593 + ... + 236101.

It is an arithmetic number, because the mean of its divisors is an integer number (2728910250).

Almost surely, 2^21420331123 is an apocalyptic number.

21420331123 is a deficient number, since it is larger than the sum of its proper divisors (410950877).

21420331123 is a wasteful number, since it uses less digits than its factorization.

21420331123 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 125861.

The product of its (nonzero) digits is 864, while the sum is 22.

Adding to 21420331123 its reverse (32113302412), we get a palindrome (53533633535).

The spelling of 21420331123 in words is "twenty-one billion, four hundred twenty million, three hundred thirty-one thousand, one hundred twenty-three".