20545515006165 has 24 divisors (see below), whose sum is σ = 37707062836248. Its totient is φ = 10313042826240.

The previous prime is 20545515006157. The next prime is 20545515006167. The reversal of 20545515006165 is 56160051554502.

It is a happy number.

20545515006165 is a `hidden beast` number, since 2 + 0 + 545 + 51 + 50 + 0 + 6 + 1 + 6 + 5 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 1181651613444 + 19363863392721 = 1087038^2 + 4400439^2 .

It is not a de Polignac number, because 20545515006165 - 2³ = 20545515006157 is a prime.

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

It is a self number, because there is not a number n which added to its sum of digits gives 20545515006165.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20545515006167) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 13428440416 + ... + 13428441945.

It is an arithmetic number, because the mean of its divisors is an integer number (1571127618177).

Almost surely, 2^{20545515006165} is an apocalyptic number.

It is an amenable number.

20545515006165 is a deficient number, since it is larger than the sum of its proper divisors (17161547830083).

20545515006165 is a wasteful number, since it uses less digits than its factorization.

20545515006165 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26856882389 (or 26856882386 counting only the distinct ones).

The product of its (nonzero) digits is 900000, while the sum is 45.

The spelling of 20545515006165 in words is "twenty trillion, five hundred forty-five billion, five hundred fifteen million, six thousand, one hundred sixty-five".