20601166521 has 8 divisors (see below), whose sum is σ = 29581162240. Its totient is φ = 12677640912.

The previous prime is 20601166513. The next prime is 20601166543. The reversal of 20601166521 is 12566110602.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 20601166521 - 2³ = 20601166513 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20601166511) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 264117481 + ... + 264117558.

It is an arithmetic number, because the mean of its divisors is an integer number (3697645280).

Almost surely, 2^20601166521 is an apocalyptic number.

It is an amenable number.

20601166521 is a deficient number, since it is larger than the sum of its proper divisors (8979995719).

20601166521 is a wasteful number, since it uses less digits than its factorization.

20601166521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 528235055.

The product of its (nonzero) digits is 4320, while the sum is 30.

The spelling of 20601166521 in words is "twenty billion, six hundred one million, one hundred sixty-six thousand, five hundred twenty-one".