21020111002 has 16 divisors (see below), whose sum is σ = 34406864352. Its totient is φ = 9551729520.

The previous prime is 21020110981. The next prime is 21020111009. The reversal of 21020111002 is 20011102012.

It is a self number, because there is not a number n which added to its sum of digits gives 21020111002.

It is not an unprimeable number, because it can be changed into a prime (21020111009) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 67428 + ... + 215839.

It is an arithmetic number, because the mean of its divisors is an integer number (2150429022).

Almost surely, 2^21020111002 is an apocalyptic number.

21020111002 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

21020111002 is a deficient number, since it is larger than the sum of its proper divisors (13386753350).

21020111002 is a wasteful number, since it uses less digits than its factorization.

21020111002 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 286653.

The product of its (nonzero) digits is 8, while the sum is 10.

Adding to 21020111002 its reverse (20011102012), we get a palindrome (41031213014).

The spelling of 21020111002 in words is "twenty-one billion, twenty million, one hundred eleven thousand, two".