20357250217 has 4 divisors (see below), whose sum is σ = 20360834260. Its totient is φ = 20353666176.

The previous prime is 20357250211. The next prime is 20357250227. The reversal of 20357250217 is 71205275302.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 18796684201 + 1560566016 = 137101^2 + 39504^2 .

It is a cyclic number.

It is not a de Polignac number, because 20357250217 - 2¹¹ = 20357248169 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20357250211) 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, 1783488 + ... + 1794865.

It is an arithmetic number, because the mean of its divisors is an integer number (5090208565).

Almost surely, 2^20357250217 is an apocalyptic number.

It is an amenable number.

20357250217 is a deficient number, since it is larger than the sum of its proper divisors (3584043).

20357250217 is an equidigital number, since it uses as much as digits as its factorization.

20357250217 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3584042.

The product of its (nonzero) digits is 29400, while the sum is 34.

The spelling of 20357250217 in words is "twenty billion, three hundred fifty-seven million, two hundred fifty thousand, two hundred seventeen".