21606255097 has 8 divisors (see below), whose sum is σ = 24771756416. Its totient is φ = 18460477152.

The previous prime is 21606255059. The next prime is 21606255103. The reversal of 21606255097 is 79055260612.

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 21606255097 - 2¹¹ = 21606253049 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21606235097) 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, 4928493 + ... + 4932874.

It is an arithmetic number, because the mean of its divisors is an integer number (3096469552).

Almost surely, 2^21606255097 is an apocalyptic number.

It is an amenable number.

21606255097 is a deficient number, since it is larger than the sum of its proper divisors (3165501319).

21606255097 is an equidigital number, since it uses as much as digits as its factorization.

21606255097 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9861687.

The product of its (nonzero) digits is 226800, while the sum is 43.

The spelling of 21606255097 in words is "twenty-one billion, six hundred six million, two hundred fifty-five thousand, ninety-seven".