21001020021002 has 32 divisors (see below), whose sum is σ = 37245864268800. Its totient is φ = 8690701501440.

The previous prime is 21001020020891. The next prime is 21001020021029. The reversal of 21001020021002 is 20012002010012.

It is a happy number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 53690933 + ... + 54080664.

It is an arithmetic number, because the mean of its divisors is an integer number (1163933258400).

Almost surely, 2^{21001020021002} is an apocalyptic number.

21001020021002 is a deficient number, since it is larger than the sum of its proper divisors (16244844247798).

21001020021002 is a wasteful number, since it uses less digits than its factorization.

21001020021002 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 107772086.

The product of its (nonzero) digits is 16, while the sum is 11.

Adding to 21001020021002 its reverse (20012002010012), we get a palindrome (41013022031014).

The spelling of 21001020021002 in words is "twenty-one trillion, one billion, twenty million, twenty-one thousand, two".