21325793209 has 4 divisors (see below), whose sum is σ = 24372335104. Its totient is φ = 18279251316.

The previous prime is 21325793189. The next prime is 21325793219. The reversal of 21325793209 is 90239752312.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21325793209 - 2²¹ = 21323696057 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21325793219) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1523270937 + ... + 1523270950.

It is an arithmetic number, because the mean of its divisors is an integer number (6093083776).

Almost surely, 2^21325793209 is an apocalyptic number.

It is an amenable number.

21325793209 is a deficient number, since it is larger than the sum of its proper divisors (3046541895).

21325793209 is an equidigital number, since it uses as much as digits as its factorization.

21325793209 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3046541894.

The product of its (nonzero) digits is 204120, while the sum is 43.

The spelling of 21325793209 in words is "twenty-one billion, three hundred twenty-five million, seven hundred ninety-three thousand, two hundred nine".