21433440020 has 12 divisors (see below), whose sum is σ = 45010224084. Its totient is φ = 8573376000.

The previous prime is 21433440019. The next prime is 21433440023. The reversal of 21433440020 is 2004433412.

It can be written as a sum of positive squares in 2 ways, for example, as 14522178064 + 6911261956 = 120508^2 + 83134^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21433440023) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 535835981 + ... + 535836020.

It is an arithmetic number, because the mean of its divisors is an integer number (3750852007).

Almost surely, 2^21433440020 is an apocalyptic number.

21433440020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21433440020 is an abundant number, since it is smaller than the sum of its proper divisors (23576784064).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21433440020 is a wasteful number, since it uses less digits than its factorization.

21433440020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1071672010 (or 1071672008 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 23.

Adding to 21433440020 its reverse (2004433412), we get a palindrome (23437873432).

The spelling of 21433440020 in words is "twenty-one billion, four hundred thirty-three million, four hundred forty thousand, twenty".