21210100212005 has 16 divisors (see below), whose sum is σ = 25994089257984. Its totient is φ = 16606779571200.

The previous prime is 21210100211981. The next prime is 21210100212019. The reversal of 21210100212005 is 50021200101212.

It is not a de Polignac number, because 21210100212005 - 2¹² = 21210100207909 is a prime.

It is a super-2 number, since 2×21210100212005² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent 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, 13941044 + ... + 15387426.

It is an arithmetic number, because the mean of its divisors is an integer number (1624630578624).

Almost surely, 2^{21210100212005} is an apocalyptic number.

It is an amenable number.

21210100212005 is a deficient number, since it is larger than the sum of its proper divisors (4783989045979).

21210100212005 is a wasteful number, since it uses less digits than its factorization.

21210100212005 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1508836.

The product of its (nonzero) digits is 80, while the sum is 17.

Adding to 21210100212005 its reverse (50021200101212), we get a palindrome (71231300313217).

The spelling of 21210100212005 in words is "twenty-one trillion, two hundred ten billion, one hundred million, two hundred twelve thousand, five".