20201985 has 24 divisors (see below), whose sum is σ = 35515584. Its totient is φ = 10620960.

The previous prime is 20201983. The next prime is 20202011. The reversal of 20201985 is 58910202.

It is not a de Polignac number, because 20201985 - 2¹ = 20201983 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20201983) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 34 + ... + 6356.

It is an arithmetic number, because the mean of its divisors is an integer number (1479816).

Almost surely, 2^20201985 is an apocalyptic number.

It is an amenable number.

20201985 is a deficient number, since it is larger than the sum of its proper divisors (15313599).

20201985 is a wasteful number, since it uses less digits than its factorization.

20201985 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6405 (or 6402 counting only the distinct ones).

The product of its (nonzero) digits is 1440, while the sum is 27.

The square root of 20201985 is about 4494.6618337757. The cubic root of 20201985 is about 272.3524886895.

It can be divided in two parts, 2020 and 1985, that added together give a triangular number (4005 = T₈₉).

The spelling of 20201985 in words is "twenty million, two hundred one thousand, nine hundred eighty-five".