20193668505 has 24 divisors (see below), whose sum is σ = 35106249672. Its totient is φ = 10737990144.

The previous prime is 20193668447. The next prime is 20193668527. The reversal of 20193668505 is 50586639102.

20193668505 is a `hidden beast` number, since 201 + 9 + 366 + 85 + 0 + 5 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 2131114896 + 18062553609 = 46164^2 + 134397^2 .

It is not a de Polignac number, because 20193668505 - 2¹² = 20193664409 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

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 23 ways as a sum of consecutive naturals, for example, 650634 + ... + 680963.

It is an arithmetic number, because the mean of its divisors is an integer number (1462760403).

Almost surely, 2^20193668505 is an apocalyptic number.

It is an amenable number.

20193668505 is a deficient number, since it is larger than the sum of its proper divisors (14912581167).

20193668505 is a wasteful number, since it uses less digits than its factorization.

20193668505 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1331945 (or 1331942 counting only the distinct ones).

The product of its (nonzero) digits is 388800, while the sum is 45.

The spelling of 20193668505 in words is "twenty billion, one hundred ninety-three million, six hundred sixty-eight thousand, five hundred five".