21021100122209 has 16 divisors (see below), whose sum is σ = 23097540721920. Its totient is φ = 18972236826000.

The previous prime is 21021100122131. The next prime is 21021100122283. The reversal of 21021100122209 is 90222100112012.

It is a cyclic number.

It is not a de Polignac number, because 21021100122209 - 2²⁴ = 21021083344993 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21021100122289) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 104622374 + ... + 104823104.

It is an arithmetic number, because the mean of its divisors is an integer number (1443596295120).

Almost surely, 2^{21021100122209} is an apocalyptic number.

It is an amenable number.

21021100122209 is a deficient number, since it is larger than the sum of its proper divisors (2076440599711).

21021100122209 is a wasteful number, since it uses less digits than its factorization.

21021100122209 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 269372.

The product of its (nonzero) digits is 288, while the sum is 23.

The spelling of 21021100122209 in words is "twenty-one trillion, twenty-one billion, one hundred million, one hundred twenty-two thousand, two hundred nine".