20440055421 has 6 divisors (see below), whose sum is σ = 29524524510. Its totient is φ = 13626703608.

The previous prime is 20440055401. The next prime is 20440055431. The reversal of 20440055421 is 12455004402.

20440055421 is a `hidden beast` number, since 204 + 400 + 5 + 54 + 2 + 1 = 666.

It can be written as a sum of positive squares in only one way, i.e., 18930732921 + 1509322500 = 137589^2 + 38850^2 .

It is not a de Polignac number, because 20440055421 - 2¹¹ = 20440053373 is a prime.

It is a super-2 number, since 2×20440055421² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20440055401) 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 5 ways as a sum of consecutive naturals, for example, 1135558626 + ... + 1135558643.

It is an arithmetic number, because the mean of its divisors is an integer number (4920754085).

Almost surely, 2^20440055421 is an apocalyptic number.

It is an amenable number.

20440055421 is a deficient number, since it is larger than the sum of its proper divisors (9084469089).

20440055421 is a wasteful number, since it uses less digits than its factorization.

20440055421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2271117275 (or 2271117272 counting only the distinct ones).

The product of its (nonzero) digits is 6400, while the sum is 27.

Adding to 20440055421 its reverse (12455004402), we get a palindrome (32895059823).

The spelling of 20440055421 in words is "twenty billion, four hundred forty million, fifty-five thousand, four hundred twenty-one".