12305440021 has 12 divisors (see below), whose sum is σ = 15156521388. Its totient is φ = 9927076992.

The previous prime is 12305439943. The next prime is 12305440033. The reversal of 12305440021 is 12004450321.

It can be written as a sum of positive squares in 2 ways, for example, as 5819553796 + 6485886225 = 76286^2 + 80535^2 .

It is not a de Polignac number, because 12305440021 - 2¹⁵ = 12305407253 is a prime.

It is a super-2 number, since 2×12305440021² (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 = 12305439974 and 12305440001.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12305440061) 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 11 ways as a sum of consecutive naturals, for example, 7385386 + ... + 7387051.

It is an arithmetic number, because the mean of its divisors is an integer number (1263043449).

Almost surely, 2^12305440021 is an apocalyptic number.

It is an amenable number.

12305440021 is a deficient number, since it is larger than the sum of its proper divisors (2851081367).

12305440021 is a wasteful number, since it uses less digits than its factorization.

12305440021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14772468 (or 14772461 counting only the distinct ones).

The product of its (nonzero) digits is 960, while the sum is 22.

Adding to 12305440021 its reverse (12004450321), we get a palindrome (24309890342).

The spelling of 12305440021 in words is "twelve billion, three hundred five million, four hundred forty thousand, twenty-one".