21372302009 has 8 divisors (see below), whose sum is σ = 21414421512. Its totient is φ = 21330207360.

The previous prime is 21372301967. The next prime is 21372302011. The reversal of 21372302009 is 90020327312.

It can be written as a sum of positive squares in 4 ways, for example, as 1483405225 + 19888896784 = 38515^2 + 141028^2 .

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 21372302009 - 2²⁰ = 21371253433 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21372302059) 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, 3516197 + ... + 3522269.

It is an arithmetic number, because the mean of its divisors is an integer number (2676802689).

Almost surely, 2^21372302009 is an apocalyptic number.

It is an amenable number.

21372302009 is a deficient number, since it is larger than the sum of its proper divisors (42119503).

21372302009 is an equidigital number, since it uses as much as digits as its factorization.

21372302009 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12427.

The product of its (nonzero) digits is 4536, while the sum is 29.

The spelling of 21372302009 in words is "twenty-one billion, three hundred seventy-two million, three hundred two thousand, nine".