20455242215 has 4 divisors (see below), whose sum is σ = 24546290664. Its totient is φ = 16364193768.

The previous prime is 20455242149. The next prime is 20455242217. The reversal of 20455242215 is 51224255402.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20455242215 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20455242217) 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 3 ways as a sum of consecutive naturals, for example, 2045524217 + ... + 2045524226.

It is an arithmetic number, because the mean of its divisors is an integer number (6136572666).

Almost surely, 2^20455242215 is an apocalyptic number.

20455242215 is a deficient number, since it is larger than the sum of its proper divisors (4091048449).

20455242215 is an equidigital number, since it uses as much as digits as its factorization.

20455242215 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4091048448.

The product of its (nonzero) digits is 32000, while the sum is 32.

Adding to 20455242215 its reverse (51224255402), we get a palindrome (71679497617).

The spelling of 20455242215 in words is "twenty billion, four hundred fifty-five million, two hundred forty-two thousand, two hundred fifteen".