21221011009 has 8 divisors (see below), whose sum is σ = 23476253760. Its totient is φ = 19020111600.

The previous prime is 21221010997. The next prime is 21221011069. The reversal of 21221011009 is 90011012212.

It is a happy number.

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 21221011009 - 2⁵ = 21221010977 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21221011069) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 13585014 + ... + 13586575.

It is an arithmetic number, because the mean of its divisors is an integer number (2934531720).

Almost surely, 2^21221011009 is an apocalyptic number.

It is an amenable number.

21221011009 is a deficient number, since it is larger than the sum of its proper divisors (2255242751).

21221011009 is a wasteful number, since it uses less digits than its factorization.

21221011009 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27171671.

The product of its (nonzero) digits is 72, while the sum is 19.

The spelling of 21221011009 in words is "twenty-one billion, two hundred twenty-one million, eleven thousand, nine".