21020044020233 has 4 divisors (see below), whose sum is σ = 21020200832148. Its totient is φ = 21019887208320.

The previous prime is 21020044020221. The next prime is 21020044020307. The reversal of 21020044020233 is 33202044002012.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 14669911137424 + 6350132882809 = 3830132^2 + 2519947^2 .

It is a cyclic number.

It is not a de Polignac number, because 21020044020233 - 2¹² = 21020044016137 is a prime.

It is a super-2 number, since 2×21020044020233² (a number of 27 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 = 21020044020199 and 21020044020208.

It is not an unprimeable number, because it can be changed into a prime (21020044220233) 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, 78204716 + ... + 78473037.

It is an arithmetic number, because the mean of its divisors is an integer number (5255050208037).

Almost surely, 2^{21020044020233} is an apocalyptic number.

It is an amenable number.

21020044020233 is a deficient number, since it is larger than the sum of its proper divisors (156811915).

21020044020233 is a wasteful number, since it uses less digits than its factorization.

21020044020233 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 156811914.

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

Adding to 21020044020233 its reverse (33202044002012), we get a palindrome (54222088022245).

The spelling of 21020044020233 in words is "twenty-one trillion, twenty billion, forty-four million, twenty thousand, two hundred thirty-three".