21000002002 has 32 divisors (see below), whose sum is σ = 36479858688. Its totient is φ = 8880592896.

The previous prime is 21000001987. The next prime is 21000002003. The reversal of 21000002002 is 20020000012.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (7).

It is not an unprimeable number, because it can be changed into a prime (21000002003) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 434703 + ... + 480589.

It is an arithmetic number, because the mean of its divisors is an integer number (1139995584).

Almost surely, 2^21000002002 is an apocalyptic number.

21000002002 is a deficient number, since it is larger than the sum of its proper divisors (15479856686).

21000002002 is a wasteful number, since it uses less digits than its factorization.

21000002002 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 46330.

The product of its (nonzero) digits is 8, while the sum is 7.

Adding to 21000002002 its reverse (20020000012), we get a palindrome (41020002014).

The spelling of 21000002002 in words is "twenty-one billion, two thousand, two".