21302442020 has 12 divisors (see below), whose sum is σ = 44735128284. Its totient is φ = 8520976800.

The previous prime is 21302442017. The next prime is 21302442023. The reversal of 21302442020 is 2024420312.

It is an interprime number because it is at equal distance from previous prime (21302442017) and next prime (21302442023).

It can be written as a sum of positive squares in 2 ways, for example, as 11399405824 + 9903036196 = 106768^2 + 99514^2 .

It is a Harshad number since it is a multiple of its sum of digits (20), and also a Moran number because the ratio is a prime number: 1065122101 = 21302442020 / (2 + 1 + 3 + 0 + 2 + 4 + 4 + 2 + 0 + 2 + 0).

It is a junction number, because it is equal to n+sod(n) for n = 21302441983 and 21302442001.

It is not an unprimeable number, because it can be changed into a prime (21302442023) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 532561031 + ... + 532561070.

It is an arithmetic number, because the mean of its divisors is an integer number (3727927357).

Almost surely, 2^21302442020 is an apocalyptic number.

21302442020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21302442020 is an abundant number, since it is smaller than the sum of its proper divisors (23432686264).

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

21302442020 is a wasteful number, since it uses less digits than its factorization.

21302442020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1065122110 (or 1065122108 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 20.

Adding to 21302442020 its reverse (2024420312), we get a palindrome (23326862332).

The spelling of 21302442020 in words is "twenty-one billion, three hundred two million, four hundred forty-two thousand, twenty".