21602546717257 has 4 divisors (see below), whose sum is σ = 23566414600656. Its totient is φ = 19638678833860.

The previous prime is 21602546717233. The next prime is 21602546717357. The reversal of 21602546717257 is 75271764520612.

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 a de Polignac number, because none of the positive numbers 2^k-21602546717257 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21602546717198 and 21602546717207.

It is not an unprimeable number, because it can be changed into a prime (21602546717207) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 981933941683 + ... + 981933941704.

It is an arithmetic number, because the mean of its divisors is an integer number (5891603650164).

Almost surely, 2^{21602546717257} is an apocalyptic number.

It is an amenable number.

21602546717257 is a deficient number, since it is larger than the sum of its proper divisors (1963867883399).

21602546717257 is a wasteful number, since it uses less digits than its factorization.

21602546717257 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1963867883398.

The product of its (nonzero) digits is 9878400, while the sum is 55.

The spelling of 21602546717257 in words is "twenty-one trillion, six hundred two billion, five hundred forty-six million, seven hundred seventeen thousand, two hundred fifty-seven".