20443312421 has 16 divisors (see below), whose sum is σ = 24130329600. Its totient is φ = 16948535040.

The previous prime is 20443312343. The next prime is 20443312423. The reversal of 20443312421 is 12421334402.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20443312421 is a prime.

It is a super-2 number, since 2×20443312421² (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 (20443312423) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 398765 + ... + 447101.

It is an arithmetic number, because the mean of its divisors is an integer number (1508145600).

Almost surely, 2^20443312421 is an apocalyptic number.

It is an amenable number.

20443312421 is a deficient number, since it is larger than the sum of its proper divisors (3687017179).

20443312421 is a wasteful number, since it uses less digits than its factorization.

20443312421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 50324.

The product of its (nonzero) digits is 4608, while the sum is 26.

Adding to 20443312421 its reverse (12421334402), we get a palindrome (32864646823).

The spelling of 20443312421 in words is "twenty billion, four hundred forty-three million, three hundred twelve thousand, four hundred twenty-one".