20321075365 has 4 divisors (see below), whose sum is σ = 24385290444. Its totient is φ = 16256860288.

The previous prime is 20321075323. The next prime is 20321075371. The reversal of 20321075365 is 56357012302.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 56357012302 = 2 ⋅28178506151.

It can be written as a sum of positive squares in 2 ways, for example, as 5903309889 + 14417765476 = 76833^2 + 120074^2 .

It is a cyclic number.

It is not a de Polignac number, because 20321075365 - 2²¹ = 20318978213 is a prime.

It is a super-2 number, since 2×20321075365² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20321075365.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2032107532 + ... + 2032107541.

It is an arithmetic number, because the mean of its divisors is an integer number (6096322611).

Almost surely, 2^20321075365 is an apocalyptic number.

It is an amenable number.

20321075365 is a deficient number, since it is larger than the sum of its proper divisors (4064215079).

20321075365 is an equidigital number, since it uses as much as digits as its factorization.

20321075365 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4064215078.

The product of its (nonzero) digits is 37800, while the sum is 34.

Adding to 20321075365 its reverse (56357012302), we get a palindrome (76678087667).

The spelling of 20321075365 in words is "twenty billion, three hundred twenty-one million, seventy-five thousand, three hundred sixty-five".