20666516125 has 32 divisors (see below), whose sum is σ = 27176423040. Its totient is φ = 15647385600.

The previous prime is 20666516033. The next prime is 20666516137. The reversal of 20666516125 is 52161566602.

It is not a de Polignac number, because 20666516125 - 2¹³ = 20666507933 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2734602 + ... + 2742148.

It is an arithmetic number, because the mean of its divisors is an integer number (849263220).

Almost surely, 2^20666516125 is an apocalyptic number.

20666516125 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

20666516125 is a deficient number, since it is larger than the sum of its proper divisors (6509906915).

20666516125 is a wasteful number, since it uses less digits than its factorization.

20666516125 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8734 (or 8724 counting only the distinct ones).

The product of its (nonzero) digits is 129600, while the sum is 40.

The spelling of 20666516125 in words is "twenty billion, six hundred sixty-six million, five hundred sixteen thousand, one hundred twenty-five".