21102020099999 has 8 divisors (see below), whose sum is σ = 21369489149760. Its totient is φ = 20834559922176.

The previous prime is 21102020099807. The next prime is 21102020100019. The reversal of 21102020099999 is 99999002020112.

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

It is a cyclic number.

It is not a de Polignac number, because 21102020099999 - 2²⁴ = 21102003322783 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21102020099999.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21102020099399) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2636087 + ... + 7010919.

It is an arithmetic number, because the mean of its divisors is an integer number (2671186143720).

Almost surely, 2^{21102020099999} is an apocalyptic number.

21102020099999 is a deficient number, since it is larger than the sum of its proper divisors (267469049761).

21102020099999 is an equidigital number, since it uses as much as digits as its factorization.

21102020099999 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4435969.

The product of its (nonzero) digits is 472392, while the sum is 53.

The spelling of 21102020099999 in words is "twenty-one trillion, one hundred two billion, twenty million, ninety-nine thousand, nine hundred ninety-nine".