21001020002 has 8 divisors (see below), whose sum is σ = 32234123856. Its totient is φ = 10256312052.

The previous prime is 21001019983. The next prime is 21001020059. The reversal of 21001020002 is 20002010012.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a super-2 number, since 2×21001020002² (a number of 21 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 122098868 + ... + 122099039.

It is an arithmetic number, because the mean of its divisors is an integer number (4029265482).

Almost surely, 2^21001020002 is an apocalyptic number.

21001020002 is a deficient number, since it is larger than the sum of its proper divisors (11233103854).

21001020002 is a wasteful number, since it uses less digits than its factorization.

21001020002 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 244197952.

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

Adding to 21001020002 its reverse (20002010012), we get a palindrome (41003030014).

The spelling of 21001020002 in words is "twenty-one billion, one million, twenty thousand, two".