20858165525 has 12 divisors (see below), whose sum is σ = 25865969472. Its totient is φ = 16685342640.

The previous prime is 20858165513. The next prime is 20858165527. The reversal of 20858165525 is 52556185802.

It is not a de Polignac number, because 20858165525 - 2¹⁴ = 20858149141 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 20858165525.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20858165527) 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 11 ways as a sum of consecutive naturals, for example, 547652 + ... + 584498.

It is an arithmetic number, because the mean of its divisors is an integer number (2155497456).

Almost surely, 2^20858165525 is an apocalyptic number.

20858165525 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

20858165525 is a deficient number, since it is larger than the sum of its proper divisors (5007803947).

20858165525 is a wasteful number, since it uses less digits than its factorization.

20858165525 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 59500 (or 59495 counting only the distinct ones).

The product of its (nonzero) digits is 960000, while the sum is 47.

The spelling of 20858165525 in words is "twenty billion, eight hundred fifty-eight million, one hundred sixty-five thousand, five hundred twenty-five".