21002033020 has 24 divisors (see below), whose sum is σ = 44107119504. Its totient is φ = 8400270336.

The previous prime is 21002032973. The next prime is 21002033023. The reversal of 21002033020 is 2033020012.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21002033023) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 455467 + ... + 499453.

It is an arithmetic number, because the mean of its divisors is an integer number (1837796646).

Almost surely, 2^21002033020 is an apocalyptic number.

21002033020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21002033020 is an abundant number, since it is smaller than the sum of its proper divisors (23105086484).

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

21002033020 is a wasteful number, since it uses less digits than its factorization.

21002033020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 67869 (or 67867 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 13.

Adding to 21002033020 its reverse (2033020012), we get a palindrome (23035053032).

The spelling of 21002033020 in words is "twenty-one billion, two million, thirty-three thousand, twenty".