21020002002 has 48 divisors (see below), whose sum is σ = 48254693760. Its totient is φ = 6590088576.

The previous prime is 21020002001. The next prime is 21020002063. The reversal of 21020002002 is 20020002012.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is not an unprimeable number, because it can be changed into a prime (21020002001) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 449899 + ... + 494417.

It is an arithmetic number, because the mean of its divisors is an integer number (1005306120).

Almost surely, 2^21020002002 is an apocalyptic number.

21020002002 is an abundant number, since it is smaller than the sum of its proper divisors (27234691758).

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

21020002002 is a wasteful number, since it uses less digits than its factorization.

21020002002 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 46087 (or 46084 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 9.

Adding to 21020002002 its reverse (20020002012), we get a palindrome (41040004014).

The spelling of 21020002002 in words is "twenty-one billion, twenty million, two thousand, two".