20985361 has 16 divisors (see below), whose sum is σ = 23390208. Its totient is φ = 18726400.

The previous prime is 20985337. The next prime is 20985373. The reversal of 20985361 is 16358902.

It is a cyclic number.

It is not a de Polignac number, because 20985361 - 2¹³ = 20977169 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20985301) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 74541 + ... + 74821.

It is an arithmetic number, because the mean of its divisors is an integer number (1461888).

Almost surely, 2^20985361 is an apocalyptic number.

It is an amenable number.

20985361 is a deficient number, since it is larger than the sum of its proper divisors (2404847).

20985361 is a wasteful number, since it uses less digits than its factorization.

20985361 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 512.

The product of its (nonzero) digits is 12960, while the sum is 34.

The square root of 20985361 is about 4580.9781706531. The cubic root of 20985361 is about 275.8282949724.

The spelling of 20985361 in words is "twenty million, nine hundred eighty-five thousand, three hundred sixty-one".