20505911495 has 4 divisors (see below), whose sum is σ = 24607093800. Its totient is φ = 16404729192.

The previous prime is 20505911473. The next prime is 20505911521. The reversal of 20505911495 is 59411950502.

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

It is a cyclic number.

It is not a de Polignac number, because 20505911495 - 2¹⁶ = 20505845959 is a prime.

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, 2050591145 + ... + 2050591154.

It is an arithmetic number, because the mean of its divisors is an integer number (6151773450).

Almost surely, 2^20505911495 is an apocalyptic number.

20505911495 is a deficient number, since it is larger than the sum of its proper divisors (4101182305).

20505911495 is an equidigital number, since it uses as much as digits as its factorization.

20505911495 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4101182304.

The product of its (nonzero) digits is 81000, while the sum is 41.

The spelling of 20505911495 in words is "twenty billion, five hundred five million, nine hundred eleven thousand, four hundred ninety-five".