20525116165 has 16 divisors (see below), whose sum is σ = 25773873408. Its totient is φ = 15661651456.

The previous prime is 20525116159. The next prime is 20525116181. The reversal of 20525116165 is 56161152502.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20525116165 is a prime.

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 20525116165.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 212209 + ... + 293398.

It is an arithmetic number, because the mean of its divisors is an integer number (1610867088).

Almost surely, 2^20525116165 is an apocalyptic number.

It is an amenable number.

20525116165 is a deficient number, since it is larger than the sum of its proper divisors (5248757243).

20525116165 is a wasteful number, since it uses less digits than its factorization.

20525116165 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 505988.

The product of its (nonzero) digits is 18000, while the sum is 34.

Adding to 20525116165 its reverse (56161152502), we get a palindrome (76686268667).

The spelling of 20525116165 in words is "twenty billion, five hundred twenty-five million, one hundred sixteen thousand, one hundred sixty-five".