21002310009 has 12 divisors (see below), whose sum is σ = 30338068800. Its totient is φ = 14000894424.

The previous prime is 21002309989. The next prime is 21002310011. The reversal of 21002310009 is 90001320012.

It is a happy number.

It is not a de Polignac number, because 21002310009 - 2²⁰ = 21001261433 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 21002309973 and 21002310000.

It is not an unprimeable number, because it can be changed into a prime (21002310059) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 232332 + ... + 309810.

It is an arithmetic number, because the mean of its divisors is an integer number (2528172400).

Almost surely, 2^21002310009 is an apocalyptic number.

It is an amenable number.

21002310009 is a deficient number, since it is larger than the sum of its proper divisors (9335758791).

21002310009 is a wasteful number, since it uses less digits than its factorization.

21002310009 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 107604 (or 107601 counting only the distinct ones).

The product of its (nonzero) digits is 108, while the sum is 18.

The spelling of 21002310009 in words is "twenty-one billion, two million, three hundred ten thousand, nine".